Reduce unnecessary usages of T-prefixed classes in classlib

classlib/src/main/java/org/teavm/classlib/java/io/TBufferedInputStream.java

@@ -15,7 +15,7 @@
  */
 package org.teavm.classlib.java.io;
 
-import org.teavm.classlib.java.lang.TString;
+import java.io.IOException;
 
 public class TBufferedInputStream extends TFilterInputStream {
     protected volatile byte[] buf;
@@ -38,16 +38,16 @@ public class TBufferedInputStream extends TFilterInputStream {
     }
 
     @Override
-    public int available() throws TIOException {
+    public int available() throws IOException {
         TInputStream localIn = in;
         if (buf == null || localIn == null) {
-            throw new TIOException(TString.wrap("Stream is closed"));
+            throw new IOException("Stream is closed");
         }
         return count - pos + localIn.available();
     }
 
     @Override
-    public void close() throws TIOException {
+    public void close() throws IOException {
         buf = null;
         TInputStream localIn = in;
         in = null;
@@ -56,7 +56,7 @@ public class TBufferedInputStream extends TFilterInputStream {
         }
     }
 
-    private int fillbuf(TInputStream localIn, byte[] localBuf) throws TIOException {
+    private int fillbuf(TInputStream localIn, byte[] localBuf) throws IOException {
         if (markpos == -1 || (pos - markpos >= marklimit)) {
             /* Mark position not set or exceeded readlimit */
             int result = localIn.read(localBuf);
@@ -103,13 +103,13 @@ public class TBufferedInputStream extends TFilterInputStream {
     }
 
     @Override
-    public synchronized int read() throws TIOException {
+    public synchronized int read() throws IOException {
         // Use local refs since buf and in may be invalidated by an
         // unsynchronized close()
         byte[] localBuf = buf;
         TInputStream localIn = in;
         if (localBuf == null || localIn == null) {
-            throw new TIOException(TString.wrap("Stream is closed"));
+            throw new IOException("Stream is closed");
         }
 
         /* Are there buffered bytes available? */
@@ -120,7 +120,7 @@ public class TBufferedInputStream extends TFilterInputStream {
         if (localBuf != buf) {
             localBuf = buf;
             if (localBuf == null) {
-                throw new TIOException(TString.wrap("Stream is closed"));
+                throw new IOException("Stream is closed");
             }
         }
 
@@ -132,10 +132,10 @@ public class TBufferedInputStream extends TFilterInputStream {
     }
 
     @Override
-    public synchronized int read(byte[] buffer, int offset, int length) throws TIOException {
+    public synchronized int read(byte[] buffer, int offset, int length) throws IOException {
         byte[] localBuf = buf;
         if (localBuf == null) {
-            throw new TIOException(TString.wrap("Stream is closed"));
+            throw new IOException("Stream is closed");
         }
         // avoid int overflow
         if (offset > buffer.length - length || offset < 0 || length < 0) {
@@ -146,7 +146,7 @@ public class TBufferedInputStream extends TFilterInputStream {
         }
         TInputStream localIn = in;
         if (localIn == null) {
-            throw new TIOException(TString.wrap("Stream is closed"));
+            throw new IOException("Stream is closed");
         }
 
         int required;
@@ -183,7 +183,7 @@ public class TBufferedInputStream extends TFilterInputStream {
                 if (localBuf != buf) {
                     localBuf = buf;
                     if (localBuf == null) {
-                        throw new TIOException(TString.wrap("Stream is closed"));
+                        throw new IOException("Stream is closed");
                     }
                 }
 
@@ -203,30 +203,30 @@ public class TBufferedInputStream extends TFilterInputStream {
     }
 
     @Override
-    public synchronized void reset() throws TIOException {
+    public synchronized void reset() throws IOException {
         if (buf == null) {
-            throw new TIOException(TString.wrap("Stream is closed"));
+            throw new IOException("Stream is closed");
         }
         if (-1 == markpos) {
-            throw new TIOException(TString.wrap("Mark has been invalidated."));
+            throw new IOException("Mark has been invalidated.");
         }
         pos = markpos;
     }
 
     @Override
-    public synchronized long skip(long amount) throws TIOException {
+    public synchronized long skip(long amount) throws IOException {
         // Use local refs since buf and in may be invalidated by an
         // unsynchronized close()
         byte[] localBuf = buf;
         TInputStream localIn = in;
         if (localBuf == null) {
-            throw new TIOException(TString.wrap("Stream is closed"));
+            throw new IOException("Stream is closed");
         }
         if (amount < 1) {
             return 0;
         }
         if (localIn == null) {
-            throw new TIOException(TString.wrap("Stream is closed"));
+            throw new IOException("Stream is closed");
         }
 
         if (count - pos >= amount) {

classlib/src/main/java/org/teavm/classlib/java/io/TBufferedOutputStream.java

@@ -16,6 +16,8 @@
 
 package org.teavm.classlib.java.io;
 
+import java.io.IOException;
+
 public class TBufferedOutputStream extends TFilterOutputStream {
     protected byte[] buf;
     protected int count;
@@ -34,13 +36,13 @@ public class TBufferedOutputStream extends TFilterOutputStream {
     }
 
     @Override
-    public void flush() throws TIOException {
+    public void flush() throws IOException {
         flushInternal();
         out.flush();
     }
 
     @Override
-    public void write(byte[] buffer, int offset, int length) throws TIOException {
+    public void write(byte[] buffer, int offset, int length) throws IOException {
         byte[] internalBuffer = buf;
 
         if (internalBuffer != null && length >= internalBuffer.length) {
@@ -62,7 +64,7 @@ public class TBufferedOutputStream extends TFilterOutputStream {
         }
 
         if (internalBuffer == null) {
-            throw new TIOException();
+            throw new IOException();
         }
 
         // flush the internal buffer first if we have not enough space left
@@ -76,7 +78,7 @@ public class TBufferedOutputStream extends TFilterOutputStream {
     }
 
     @Override
-    public void close() throws TIOException {
+    public void close() throws IOException {
         if (buf == null) {
             return;
         }
@@ -89,10 +91,10 @@ public class TBufferedOutputStream extends TFilterOutputStream {
     }
 
     @Override
-    public void write(int oneByte) throws TIOException {
+    public void write(int oneByte) throws IOException {
         byte[] internalBuffer = buf;
         if (internalBuffer == null) {
-            throw new TIOException();
+            throw new IOException();
         }
 
         if (count == internalBuffer.length) {
@@ -102,7 +104,7 @@ public class TBufferedOutputStream extends TFilterOutputStream {
         internalBuffer[count++] = (byte) oneByte;
     }
 
-    private void flushInternal() throws TIOException {
+    private void flushInternal() throws IOException {
         if (count > 0) {
             out.write(buf, 0, count);
             count = 0;

classlib/src/main/java/org/teavm/classlib/java/io/TBufferedReader.java

@@ -15,9 +15,9 @@
  */
 package org.teavm.classlib.java.io;
 
+import java.io.IOException;
 import org.teavm.classlib.java.lang.TIllegalArgumentException;
 import org.teavm.classlib.java.lang.TMath;
-import org.teavm.classlib.java.lang.TString;
 import org.teavm.classlib.java.lang.TStringBuilder;
 import org.teavm.classlib.java.util.TArrays;
 
@@ -42,7 +42,7 @@ public class TBufferedReader extends TReader {
     }
 
     @Override
-    public int read() throws TIOException {
+    public int read() throws IOException {
         requireOpened();
         if (index >= count) {
             if (!fillBuffer(0)) {
@@ -53,14 +53,14 @@ public class TBufferedReader extends TReader {
     }
 
     @Override
-    public void close() throws TIOException {
+    public void close() throws IOException {
         requireOpened();
         innerReader.close();
         innerReader = null;
     }
 
     @Override
-    public int read(char[] cbuf, int off, int len) throws TIOException {
+    public int read(char[] cbuf, int off, int len) throws IOException {
         requireOpened();
         if (index == count && eof) {
             return -1;
@@ -79,7 +79,7 @@ public class TBufferedReader extends TReader {
         return charsRead;
     }
 
-    public TString readLine() throws TIOException {
+    public String readLine() throws IOException {
         requireOpened();
         if (eof && index >= count) {
             return null;
@@ -108,11 +108,11 @@ public class TBufferedReader extends TReader {
                 line.append(ch);
             }
         }
-        return TString.wrap(line.toString());
+        return line.toString();
     }
 
     @Override
-    public long skip(long n) throws TIOException {
+    public long skip(long n) throws IOException {
         requireOpened();
         if (n < count - index) {
             index += n;
@@ -135,7 +135,7 @@ public class TBufferedReader extends TReader {
     }
 
     @Override
-    public void mark(int readAheadLimit) throws TIOException {
+    public void mark(int readAheadLimit) throws IOException {
         if (readAheadLimit > buffer.length) {
             buffer = TArrays.copyOf(buffer, readAheadLimit);
         }
@@ -149,14 +149,14 @@ public class TBufferedReader extends TReader {
     }
 
     @Override
-    public void reset() throws TIOException {
+    public void reset() throws IOException {
         if (mark == -1) {
-            throw new TIOException();
+            throw new IOException();
         }
         index = mark;
     }
 
-    private boolean fillBuffer(int offset) throws TIOException {
+    private boolean fillBuffer(int offset) throws IOException {
         if (eof) {
             return false;
         }
@@ -177,9 +177,9 @@ public class TBufferedReader extends TReader {
         return true;
     }
 
-    private void requireOpened() {
+    private void requireOpened() throws IOException {
         if (innerReader == null) {
-            throw new TIOException();
+            throw new IOException();
         }
     }
 }

classlib/src/main/java/org/teavm/classlib/java/io/TByteArrayOutputStream.java

@@ -15,6 +15,7 @@
  */
 package org.teavm.classlib.java.io;
 
+import java.io.IOException;
 import org.teavm.classlib.java.lang.TMath;
 import org.teavm.classlib.java.lang.TString;
 import org.teavm.classlib.java.util.TArrays;
@@ -65,7 +66,7 @@ public class TByteArrayOutputStream extends TOutputStream {
         return new TString(buf, 0, count, charsetName);
     }
 
-    public void writeTo(TOutputStream out) throws TIOException {
+    public void writeTo(TOutputStream out) throws IOException {
         out.write(buf, 0, count);
     }
 

classlib/src/main/java/org/teavm/classlib/java/io/TCloseable.java

@@ -15,9 +15,10 @@
  */
 package org.teavm.classlib.java.io;
 
+import java.io.IOException;
 import org.teavm.classlib.java.lang.TAutoCloseable;
 
 public interface TCloseable extends TAutoCloseable {
     @Override
-    void close() throws TIOException;
+    void close() throws IOException;
 }

classlib/src/main/java/org/teavm/classlib/java/io/TDataInput.java

@@ -15,36 +15,36 @@
  */
 package org.teavm.classlib.java.io;
 
-import org.teavm.classlib.java.lang.TString;
+import java.io.IOException;
 
 public interface TDataInput {
-    void readFully(byte[] b) throws TIOException;
+    void readFully(byte[] b) throws IOException;
 
-    void readFully(byte[] b, int off, int len) throws TIOException;
+    void readFully(byte[] b, int off, int len) throws IOException;
 
-    int skipBytes(int n) throws TIOException;
+    int skipBytes(int n) throws IOException;
 
-    boolean readBoolean() throws TIOException;
+    boolean readBoolean() throws IOException;
 
-    byte readByte() throws TIOException;
+    byte readByte() throws IOException;
 
-    int readUnsignedByte() throws TIOException;
+    int readUnsignedByte() throws IOException;
 
-    short readShort() throws TIOException;
+    short readShort() throws IOException;
 
-    int readUnsignedShort() throws TIOException;
+    int readUnsignedShort() throws IOException;
 
-    char readChar() throws TIOException;
+    char readChar() throws IOException;
 
-    int readInt() throws TIOException;
+    int readInt() throws IOException;
 
-    long readLong() throws TIOException;
+    long readLong() throws IOException;
 
-    float readFloat() throws TIOException;
+    float readFloat() throws IOException;
 
-    double readDouble() throws TIOException;
+    double readDouble() throws IOException;
 
-    TString readLine() throws TIOException;
+    String readLine() throws IOException;
 
-    TString readUTF() throws TIOException;
+    String readUTF() throws IOException;
 }

classlib/src/main/java/org/teavm/classlib/java/io/TDataInputStream.java

@@ -15,6 +15,7 @@
  */
 package org.teavm.classlib.java.io;
 
+import java.io.IOException;
 import org.teavm.classlib.java.lang.*;
 
 public class TDataInputStream extends TFilterInputStream implements TDataInput {
@@ -26,17 +27,17 @@ public class TDataInputStream extends TFilterInputStream implements TDataInput {
     }
 
     @Override
-    public final int read(byte[] buffer) throws TIOException {
+    public final int read(byte[] buffer) throws IOException {
         return in.read(buffer, 0, buffer.length);
     }
 
     @Override
-    public final int read(byte[] buffer, int offset, int length) throws TIOException {
+    public final int read(byte[] buffer, int offset, int length) throws IOException {
         return in.read(buffer, offset, length);
     }
 
     @Override
-    public final boolean readBoolean() throws TIOException {
+    public final boolean readBoolean() throws IOException {
         int temp = in.read();
         if (temp < 0) {
             throw new TEOFException();
@@ -45,7 +46,7 @@ public class TDataInputStream extends TFilterInputStream implements TDataInput {
     }
 
     @Override
-    public final byte readByte() throws TIOException {
+    public final byte readByte() throws IOException {
         int temp = in.read();
         if (temp < 0) {
             throw new TEOFException();
@@ -53,7 +54,7 @@ public class TDataInputStream extends TFilterInputStream implements TDataInput {
         return (byte) temp;
     }
 
-    private int readToBuff(int count) throws TIOException {
+    private int readToBuff(int count) throws IOException {
         int offset = 0;
         while (offset < count) {
             int bytesRead = in.read(buff, offset, count - offset);
@@ -66,7 +67,7 @@ public class TDataInputStream extends TFilterInputStream implements TDataInput {
     }
 
     @Override
-    public final char readChar() throws TIOException {
+    public final char readChar() throws IOException {
         if (readToBuff(2) < 0) {
             throw new TEOFException();
         }
@@ -74,22 +75,22 @@ public class TDataInputStream extends TFilterInputStream implements TDataInput {
     }
 
     @Override
-    public final double readDouble() throws TIOException {
+    public final double readDouble() throws IOException {
         return TDouble.longBitsToDouble(readLong());
     }
 
     @Override
-    public final float readFloat() throws TIOException {
+    public final float readFloat() throws IOException {
         return TFloat.intBitsToFloat(readInt());
     }
 
     @Override
-    public final void readFully(byte[] buffer) throws TIOException {
+    public final void readFully(byte[] buffer) throws IOException {
         readFully(buffer, 0, buffer.length);
     }
 
     @Override
-    public final void readFully(byte[] buffer, int offset, int length) throws TIOException {
+    public final void readFully(byte[] buffer, int offset, int length) throws IOException {
         if (length < 0) {
             throw new TIndexOutOfBoundsException();
         }
@@ -116,7 +117,7 @@ public class TDataInputStream extends TFilterInputStream implements TDataInput {
     }
 
     @Override
-    public final int readInt() throws TIOException {
+    public final int readInt() throws IOException {
         if (readToBuff(4) < 0) {
             throw new TEOFException();
         }
@@ -125,7 +126,7 @@ public class TDataInputStream extends TFilterInputStream implements TDataInput {
 
     @Override
     @Deprecated
-    public final TString readLine() throws TIOException {
+    public final String readLine() throws IOException {
         TStringBuilder line = new TStringBuilder(80);
         boolean foundTerminator = false;
         while (true) {
@@ -135,11 +136,11 @@ public class TDataInputStream extends TFilterInputStream implements TDataInput {
                     if (line.length() == 0 && !foundTerminator) {
                         return null;
                     }
-                    return TString.wrap(line.toString());
+                    return line.toString();
                 case (byte) '\r':
                     if (foundTerminator) {
                         ((TPushbackInputStream) in).unread(nextByte);
-                        return TString.wrap(line.toString());
+                        return line.toString();
                     }
                     foundTerminator = true;
                     /* Have to be able to peek ahead one byte */
@@ -148,11 +149,11 @@ public class TDataInputStream extends TFilterInputStream implements TDataInput {
                     }
                     break;
                 case (byte) '\n':
-                    return TString.wrap(line.toString());
+                    return line.toString();
                 default:
                     if (foundTerminator) {
                         ((TPushbackInputStream) in).unread(nextByte);
-                        return TString.wrap(line.toString());
+                        return line.toString();
                     }
                     line.append((char) nextByte);
             }
@@ -160,7 +161,7 @@ public class TDataInputStream extends TFilterInputStream implements TDataInput {
     }
 
     @Override
-    public final long readLong() throws TIOException {
+    public final long readLong() throws IOException {
         if (readToBuff(8) < 0) {
             throw new TEOFException();
         }
@@ -172,7 +173,7 @@ public class TDataInputStream extends TFilterInputStream implements TDataInput {
     }
 
     @Override
-    public final short readShort() throws TIOException {
+    public final short readShort() throws IOException {
         if (readToBuff(2) < 0) {
             throw new TEOFException();
         }
@@ -180,7 +181,7 @@ public class TDataInputStream extends TFilterInputStream implements TDataInput {
     }
 
     @Override
-    public final int readUnsignedByte() throws TIOException {
+    public final int readUnsignedByte() throws IOException {
         int temp = in.read();
         if (temp < 0) {
             throw new TEOFException();
@@ -189,7 +190,7 @@ public class TDataInputStream extends TFilterInputStream implements TDataInput {
     }
 
     @Override
-    public final int readUnsignedShort() throws TIOException {
+    public final int readUnsignedShort() throws IOException {
         if (readToBuff(2) < 0) {
             throw new TEOFException();
         }
@@ -197,15 +198,15 @@ public class TDataInputStream extends TFilterInputStream implements TDataInput {
     }
 
     @Override
-    public final TString readUTF() throws TIOException {
+    public final String readUTF() throws IOException {
         return decodeUTF(readUnsignedShort());
     }
 
-    TString decodeUTF(int utfSize) throws TIOException {
+    String decodeUTF(int utfSize) throws IOException {
         return decodeUTF(utfSize, this);
     }
 
-    private static TString decodeUTF(int utfSize, TDataInput in) throws TIOException {
+    private static String decodeUTF(int utfSize, TDataInput in) throws IOException {
         byte[] buf = new byte[utfSize];
         char[] out = new char[utfSize];
         in.readFully(buf, 0, utfSize);
@@ -213,12 +214,12 @@ public class TDataInputStream extends TFilterInputStream implements TDataInput {
         return convertUTF8WithBuf(buf, out, 0, utfSize);
     }
 
-    public static final TString readUTF(TDataInput in) throws TIOException {
+    public static String readUTF(TDataInput in) throws IOException {
         return decodeUTF(in.readUnsignedShort(), in);
     }
 
     @Override
-    public final int skipBytes(int count) throws TIOException {
+    public final int skipBytes(int count) throws IOException {
         int skipped = 0;
 
         while (skipped < count) {
@@ -234,7 +235,7 @@ public class TDataInputStream extends TFilterInputStream implements TDataInput {
         return skipped;
     }
 
-    private static TString convertUTF8WithBuf(byte[] buf, char[] out, int offset, int utfSize)
+    private static String convertUTF8WithBuf(byte[] buf, char[] out, int offset, int utfSize)
             throws TUTFDataFormatException {
         int count = 0;
         int s = 0;
@@ -247,27 +248,27 @@ public class TDataInputStream extends TFilterInputStream implements TDataInput {
                 s++;
             } else if ((a & 0xe0) == 0xc0) {
                 if (count >= utfSize) {
-                    throw new TUTFDataFormatException(TString.wrap("End of stream reached"));
+                    throw new TUTFDataFormatException("End of stream reached");
                 }
                 int b = buf[offset + count++];
                 if ((b & 0xC0) != 0x80) {
-                    throw new TUTFDataFormatException(TString.wrap("Malformed UTF-8 sequence"));
+                    throw new TUTFDataFormatException("Malformed UTF-8 sequence");
                 }
                 out[s++] = (char) (((a & 0x1F) << 6) | (b & 0x3F));
             } else if ((a & 0xf0) == 0xe0) {
                 if (count + 1 >= utfSize) {
-                    throw new TUTFDataFormatException(TString.wrap("Malformed UTF-8 sequence"));
+                    throw new TUTFDataFormatException("Malformed UTF-8 sequence");
                 }
                 int b = buf[offset + count++];
                 int c = buf[offset + count++];
                 if (((b & 0xC0) != 0x80) || ((c & 0xC0) != 0x80)) {
-                    throw new TUTFDataFormatException(TString.wrap("Malformed UTF-8 sequence"));
+                    throw new TUTFDataFormatException("Malformed UTF-8 sequence");
                 }
                 out[s++] = (char) (((a & 0x0F) << 12) | ((b & 0x3F) << 6) | (c & 0x3F));
             } else {
-                throw new TUTFDataFormatException(TString.wrap("Malformed UTF-8 sequence"));
+                throw new TUTFDataFormatException("Malformed UTF-8 sequence");
             }
         }
-        return new TString(out, 0, s);
+        return new String(out, 0, s);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/io/TDataOutput.java

@@ -15,34 +15,35 @@
  */
 package org.teavm.classlib.java.io;
 
+import java.io.IOException;
 import org.teavm.classlib.java.lang.TString;
 
 public interface TDataOutput {
-    void write(int b) throws TIOException;
+    void write(int b) throws IOException;
 
-    void write(byte[] b) throws TIOException;
+    void write(byte[] b) throws IOException;
 
-    void write(byte[] b, int off, int len) throws TIOException;
+    void write(byte[] b, int off, int len) throws IOException;
 
-    void writeBoolean(boolean v) throws TIOException;
+    void writeBoolean(boolean v) throws IOException;
 
-    void writeByte(int v) throws TIOException;
+    void writeByte(int v) throws IOException;
 
-    void writeShort(int v) throws TIOException;
+    void writeShort(int v) throws IOException;
 
-    void writeChar(int v) throws TIOException;
+    void writeChar(int v) throws IOException;
 
-    void writeInt(int v) throws TIOException;
+    void writeInt(int v) throws IOException;
 
-    void writeLong(long v) throws TIOException;
+    void writeLong(long v) throws IOException;
 
-    void writeFloat(float v) throws TIOException;
+    void writeFloat(float v) throws IOException;
 
-    void writeDouble(double v) throws TIOException;
+    void writeDouble(double v) throws IOException;
 
-    void writeBytes(TString s) throws TIOException;
+    void writeBytes(TString s) throws IOException;
 
-    void writeChars(TString s) throws TIOException;
+    void writeChars(TString s) throws IOException;
 
-    void writeUTF(TString s) throws TIOException;
+    void writeUTF(TString s) throws IOException;
 }

classlib/src/main/java/org/teavm/classlib/java/io/TDataOutputStream.java

@@ -14,6 +14,7 @@
  *  limitations under the License.
  */
 package org.teavm.classlib.java.io;
+import java.io.IOException;
 import org.teavm.classlib.java.lang.*;
 
 public class TDataOutputStream extends TFilterOutputStream implements TDataOutput {
@@ -29,7 +30,7 @@ public class TDataOutputStream extends TFilterOutputStream implements TDataOutpu
     }
 
     @Override
-    public void flush() throws TIOException {
+    public void flush() throws IOException {
         super.flush();
     }
 
@@ -41,7 +42,7 @@ public class TDataOutputStream extends TFilterOutputStream implements TDataOutpu
     }
 
     @Override
-    public void write(byte[] buffer, int offset, int count) throws TIOException {
+    public void write(byte[] buffer, int offset, int count) throws IOException {
         if (buffer == null) {
             throw new TNullPointerException();
         }
@@ -50,25 +51,25 @@ public class TDataOutputStream extends TFilterOutputStream implements TDataOutpu
     }
 
     @Override
-    public void write(int oneByte) throws TIOException {
+    public void write(int oneByte) throws IOException {
         out.write(oneByte);
         written++;
     }
 
     @Override
-    public final void writeBoolean(boolean val) throws TIOException {
+    public final void writeBoolean(boolean val) throws IOException {
         out.write(val ? 1 : 0);
         written++;
     }
 
     @Override
-    public final void writeByte(int val) throws TIOException {
+    public final void writeByte(int val) throws IOException {
         out.write(val);
         written++;
     }
 
     @Override
-    public final void writeBytes(TString str) throws TIOException {
+    public final void writeBytes(TString str) throws IOException {
         if (str.length() == 0) {
             return;
         }
@@ -81,7 +82,7 @@ public class TDataOutputStream extends TFilterOutputStream implements TDataOutpu
     }
 
     @Override
-    public final void writeChar(int val) throws TIOException {
+    public final void writeChar(int val) throws IOException {
         buff[0] = (byte) (val >> 8);
         buff[1] = (byte) val;
         out.write(buff, 0, 2);
@@ -89,7 +90,7 @@ public class TDataOutputStream extends TFilterOutputStream implements TDataOutpu
     }
 
     @Override
-    public final void writeChars(TString str) throws TIOException {
+    public final void writeChars(TString str) throws IOException {
         byte[] newBytes = new byte[str.length() * 2];
         for (int index = 0; index < str.length(); index++) {
             int newIndex = index == 0 ? index : index * 2;
@@ -101,17 +102,17 @@ public class TDataOutputStream extends TFilterOutputStream implements TDataOutpu
     }
 
     @Override
-    public final void writeDouble(double val) throws TIOException {
+    public final void writeDouble(double val) throws IOException {
         writeLong(TDouble.doubleToLongBits(val));
     }
 
     @Override
-    public final void writeFloat(float val) throws TIOException {
+    public final void writeFloat(float val) throws IOException {
         writeInt(TFloat.floatToIntBits(val));
     }
 
     @Override
-    public final void writeInt(int val) throws TIOException {
+    public final void writeInt(int val) throws IOException {
         buff[0] = (byte) (val >> 24);
         buff[1] = (byte) (val >> 16);
         buff[2] = (byte) (val >> 8);
@@ -121,7 +122,7 @@ public class TDataOutputStream extends TFilterOutputStream implements TDataOutpu
     }
 
     @Override
-    public final void writeLong(long val) throws TIOException {
+    public final void writeLong(long val) throws IOException {
         buff[0] = (byte) (val >> 56);
         buff[1] = (byte) (val >> 48);
         buff[2] = (byte) (val >> 40);
@@ -134,7 +135,7 @@ public class TDataOutputStream extends TFilterOutputStream implements TDataOutpu
         written += 8;
     }
 
-    int writeLongToBuffer(long val, byte[] buffer, int offset) throws TIOException {
+    int writeLongToBuffer(long val, byte[] buffer, int offset) throws IOException {
         buffer[offset++] = (byte) (val >> 56);
         buffer[offset++] = (byte) (val >> 48);
         buffer[offset++] = (byte) (val >> 40);
@@ -147,24 +148,24 @@ public class TDataOutputStream extends TFilterOutputStream implements TDataOutpu
     }
 
     @Override
-    public final void writeShort(int val) throws TIOException {
+    public final void writeShort(int val) throws IOException {
         buff[0] = (byte) (val >> 8);
         buff[1] = (byte) val;
         out.write(buff, 0, 2);
         written += 2;
     }
 
-    int writeShortToBuffer(int val, byte[] buffer, int offset) throws TIOException {
+    int writeShortToBuffer(int val, byte[] buffer, int offset) throws IOException {
         buffer[offset++] = (byte) (val >> 8);
         buffer[offset++] = (byte) val;
         return offset;
     }
 
     @Override
-    public final void writeUTF(TString str) throws TIOException {
+    public final void writeUTF(TString str) throws IOException {
         long utfCount = countUTFBytes(str);
         if (utfCount > 65535) {
-            throw new TIOException(TString.wrap("UTF Error"));
+            throw new IOException("UTF Error");
         }
         byte[] buffer = new byte[(int) utfCount + 2];
         int offset = 0;
@@ -189,7 +190,7 @@ public class TDataOutputStream extends TFilterOutputStream implements TDataOutpu
         return utfCount;
     }
 
-    int writeUTFBytesToBuffer(TString str, byte[] buffer, int offset) throws TIOException {
+    int writeUTFBytesToBuffer(TString str, byte[] buffer, int offset) throws IOException {
         int length = str.length();
         for (int i = 0; i < length; i++) {
             int charValue = str.charAt(i);

classlib/src/main/java/org/teavm/classlib/java/io/TEOFException.java

@@ -15,16 +15,16 @@
  */
 package org.teavm.classlib.java.io;
 
-import org.teavm.classlib.java.lang.TString;
+import java.io.IOException;
 
-public class TEOFException extends TIOException {
+public class TEOFException extends IOException {
     private static final long serialVersionUID = 3045477060413545010L;
 
     public TEOFException() {
         super();
     }
 
-    public TEOFException(TString message) {
+    public TEOFException(String message) {
         super(message);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/io/TFilterInputStream.java

@@ -15,6 +15,8 @@
  */
 package org.teavm.classlib.java.io;
 
+import java.io.IOException;
+
 public class TFilterInputStream extends TInputStream {
     protected volatile TInputStream in;
 
@@ -23,12 +25,12 @@ public class TFilterInputStream extends TInputStream {
     }
 
     @Override
-    public int available() throws TIOException {
+    public int available() throws IOException {
         return in.available();
     }
 
     @Override
-    public void close() throws TIOException {
+    public void close() throws IOException {
         in.close();
     }
 
@@ -43,27 +45,27 @@ public class TFilterInputStream extends TInputStream {
     }
 
     @Override
-    public int read() throws TIOException {
+    public int read() throws IOException {
         return in.read();
     }
 
     @Override
-    public int read(byte[] buffer) throws TIOException {
+    public int read(byte[] buffer) throws IOException {
         return read(buffer, 0, buffer.length);
     }
 
     @Override
-    public int read(byte[] buffer, int offset, int count) throws TIOException {
+    public int read(byte[] buffer, int offset, int count) throws IOException {
         return in.read(buffer, offset, count);
     }
 
     @Override
-    public synchronized void reset() throws TIOException {
+    public synchronized void reset() throws IOException {
         in.reset();
     }
 
     @Override
-    public long skip(long count) throws TIOException {
+    public long skip(long count) throws IOException {
         return in.skip(count);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/io/TFilterOutputStream.java

@@ -15,6 +15,8 @@
  */
 package org.teavm.classlib.java.io;
 
+import java.io.IOException;
+
 public class TFilterOutputStream extends TOutputStream {
     protected TOutputStream out;
 
@@ -23,22 +25,22 @@ public class TFilterOutputStream extends TOutputStream {
     }
 
     @Override
-    public void write(int b) throws TIOException {
+    public void write(int b) throws IOException {
         out.write(b);
     }
 
     @Override
-    public void close() throws TIOException {
+    public void close() throws IOException {
         try {
             out.flush();
-        } catch (TIOException e) {
+        } catch (IOException e) {
             // do nothing
         }
         out.close();
     }
 
     @Override
-    public void flush() throws TIOException {
+    public void flush() throws IOException {
         out.flush();
     }
 }

classlib/src/main/java/org/teavm/classlib/java/io/TFlushable.java

@@ -15,6 +15,8 @@
  */
 package org.teavm.classlib.java.io;
 
+import java.io.IOException;
+
 public interface TFlushable {
-    void flush() throws TIOException;
+    void flush() throws IOException;
 }

classlib/src/main/java/org/teavm/classlib/java/io/TIOException.java

@@ -15,26 +15,22 @@
  */
 package org.teavm.classlib.java.io;
 
-import org.teavm.classlib.java.lang.TException;
+public class TIOException extends Exception {
-import org.teavm.classlib.java.lang.TString;
-import org.teavm.classlib.java.lang.TThrowable;
-
-public class TIOException extends TException {
     private static final long serialVersionUID = 3626109154700059455L;
 
     public TIOException() {
         super();
     }
 
-    public TIOException(TString message, TThrowable cause) {
+    public TIOException(String message, Throwable cause) {
         super(message, cause);
     }
 
-    public TIOException(TString message) {
+    public TIOException(String message) {
         super(message);
     }
 
-    public TIOException(TThrowable cause) {
+    public TIOException(Throwable cause) {
         super(cause);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/io/TInputStream.java

@@ -15,6 +15,7 @@
  */
 package org.teavm.classlib.java.io;
 
+import java.io.IOException;
 import org.teavm.classlib.java.lang.TInteger;
 import org.teavm.classlib.java.lang.TObject;
 
@@ -22,13 +23,13 @@ public abstract class TInputStream extends TObject implements TCloseable {
     public TInputStream() {
     }
 
-    public abstract int read() throws TIOException;
+    public abstract int read() throws IOException;
 
-    public int read(byte[] b) throws TIOException {
+    public int read(byte[] b) throws IOException {
         return read(b, 0, b.length);
     }
 
-    public int read(byte[] b, int off, int len) throws TIOException {
+    public int read(byte[] b, int off, int len) throws IOException {
         for (int i = 0; i < len; ++i) {
             int bt = read();
             if (bt < 0) {
@@ -39,7 +40,7 @@ public abstract class TInputStream extends TObject implements TCloseable {
         return len > 0 ? len : -1;
     }
 
-    public long skip(long n) throws TIOException {
+    public long skip(long n) throws IOException {
         if (n < TInteger.MAX_VALUE) {
             return skip((int) n);
         } else {
@@ -52,7 +53,7 @@ public abstract class TInputStream extends TObject implements TCloseable {
         }
     }
 
-    private int skip(int n) throws TIOException {
+    private int skip(int n) throws IOException {
         for (int i = 0; i < n; ++i) {
             if (read() < 0) {
                 return i;
@@ -61,19 +62,19 @@ public abstract class TInputStream extends TObject implements TCloseable {
         return n;
     }
 
-    public int available() throws TIOException {
+    public int available() throws IOException {
         return 0;
     }
 
     @Override
-    public void close() throws TIOException {
+    public void close() throws IOException {
     }
 
     public void mark(@SuppressWarnings("unused") int readlimit) {
     }
 
-    public void reset() throws TIOException {
+    public void reset() throws IOException {
-        throw new TIOException();
+        throw new IOException();
     }
 
     public boolean markSupported() {

classlib/src/main/java/org/teavm/classlib/java/io/TInputStreamReader.java

@@ -15,7 +15,7 @@
  */
 package org.teavm.classlib.java.io;
 
-import org.teavm.classlib.java.lang.TString;
+import java.io.IOException;
 import org.teavm.classlib.java.nio.TByteBuffer;
 import org.teavm.classlib.java.nio.TCharBuffer;
 import org.teavm.classlib.java.nio.charset.TCharset;
@@ -34,7 +34,7 @@ public class TInputStreamReader extends TReader {
     private boolean streamEof;
     private boolean eof;
 
-    public TInputStreamReader(TInputStream in, TString charsetName) throws TUnsupportedEncodingException {
+    public TInputStreamReader(TInputStream in, String charsetName) throws TUnsupportedEncodingException {
         this(in, getCharset(charsetName));
     }
 
@@ -55,7 +55,7 @@ public class TInputStreamReader extends TReader {
         inBuffer.position(inBuffer.limit());
     }
 
-    private static TCharset getCharset(TString charsetName) throws TUnsupportedEncodingException  {
+    private static TCharset getCharset(String charsetName) throws TUnsupportedEncodingException  {
         try {
             return TCharset.forName(charsetName.toString());
         } catch (TUnsupportedCharsetException e) {
@@ -63,17 +63,17 @@ public class TInputStreamReader extends TReader {
         }
     }
 
-    public TString getEncoding() {
+    public String getEncoding() {
-        return TString.wrap(decoder.charset().name());
+        return decoder.charset().name();
     }
 
     @Override
-    public void close() throws TIOException {
+    public void close() throws IOException {
         stream.close();
     }
 
     @Override
-    public int read() throws TIOException {
+    public int read() throws IOException {
         if (eof && !outBuffer.hasRemaining()) {
             return -1;
         }
@@ -84,7 +84,7 @@ public class TInputStreamReader extends TReader {
     }
 
     @Override
-    public int read(char[] cbuf, int off, int len) throws TIOException {
+    public int read(char[] cbuf, int off, int len) throws IOException {
         if (eof && !outBuffer.hasRemaining()) {
             return -1;
         }
@@ -101,7 +101,7 @@ public class TInputStreamReader extends TReader {
         return bytesRead;
     }
 
-    private boolean fillBuffer() throws TIOException {
+    private boolean fillBuffer() throws IOException {
         if (eof) {
             return false;
         }
@@ -121,7 +121,7 @@ public class TInputStreamReader extends TReader {
         return true;
     }
 
-    private boolean fillReadBuffer() throws TIOException {
+    private boolean fillReadBuffer() throws IOException {
         if (streamEof) {
             return false;
         }
@@ -143,7 +143,7 @@ public class TInputStreamReader extends TReader {
     }
 
     @Override
-    public boolean ready() throws TIOException {
+    public boolean ready() throws IOException {
         return outBuffer.hasRemaining() || inBuffer.hasRemaining();
     }
 }

classlib/src/main/java/org/teavm/classlib/java/io/TOutputStream.java

@@ -15,26 +15,27 @@
  */
 package org.teavm.classlib.java.io;
 
+import java.io.IOException;
 import org.teavm.classlib.java.lang.TObject;
 
 public abstract class TOutputStream extends TObject implements TCloseable, TFlushable {
-    public abstract void write(int b) throws TIOException;
+    public abstract void write(int b) throws IOException;
 
-    public void write(byte[] b) throws TIOException {
+    public void write(byte[] b) throws IOException {
         write(b, 0, b.length);
     }
 
-    public void write(byte[] b, int off, int len) throws TIOException {
+    public void write(byte[] b, int off, int len) throws IOException {
         for (int i = 0; i < len; ++i) {
             write(b[off++]);
         }
     }
 
     @Override
-    public void close() throws TIOException {
+    public void close() throws IOException {
     }
 
     @Override
-    public void flush() throws TIOException {
+    public void flush() throws IOException {
     }
 }

classlib/src/main/java/org/teavm/classlib/java/io/TOutputStreamWriter.java

@@ -15,10 +15,14 @@
  */
 package org.teavm.classlib.java.io;
 
-import org.teavm.classlib.java.lang.TString;
+import java.io.IOException;
 import org.teavm.classlib.java.nio.TByteBuffer;
 import org.teavm.classlib.java.nio.TCharBuffer;
-import org.teavm.classlib.java.nio.charset.*;
+import org.teavm.classlib.java.nio.charset.TCharset;
+import org.teavm.classlib.java.nio.charset.TCharsetEncoder;
+import org.teavm.classlib.java.nio.charset.TCodingErrorAction;
+import org.teavm.classlib.java.nio.charset.TIllegalCharsetNameException;
+import org.teavm.classlib.java.nio.charset.TUnsupportedCharsetException;
 import org.teavm.classlib.java.nio.charset.impl.TUTF8Charset;
 
 public class TOutputStreamWriter extends TWriter {
@@ -61,12 +65,12 @@ public class TOutputStreamWriter extends TWriter {
         try {
             return TCharset.forName(charsetName);
         } catch (TUnsupportedCharsetException | TIllegalCharsetNameException e) {
-            throw new TUnsupportedEncodingException(TString.wrap(charsetName));
+            throw new TUnsupportedEncodingException(charsetName);
         }
     }
 
     @Override
-    public void close() throws TIOException {
+    public void close() throws IOException {
         if (!closed) {
             flush();
             closed = true;
@@ -76,7 +80,7 @@ public class TOutputStreamWriter extends TWriter {
     }
 
     @Override
-    public void flush() throws TIOException {
+    public void flush() throws IOException {
         checkStatus();
         if (buffer.position() > 0) {
             out.write(bufferData, 0, buffer.position());
@@ -85,9 +89,9 @@ public class TOutputStreamWriter extends TWriter {
         out.flush();
     }
 
-    private void checkStatus() throws TIOException {
+    private void checkStatus() throws IOException {
         if (closed) {
-            throw new TIOException(TString.wrap("Writer already closed"));
+            throw new IOException("Writer already closed");
         }
     }
 
@@ -96,7 +100,7 @@ public class TOutputStreamWriter extends TWriter {
     }
 
     @Override
-    public void write(char[] buf, int offset, int count) throws TIOException {
+    public void write(char[] buf, int offset, int count) throws IOException {
         synchronized (lock) {
             checkStatus();
             if (buf == null) {
@@ -116,13 +120,13 @@ public class TOutputStreamWriter extends TWriter {
     }
 
     @Override
-    public void write(int oneChar) throws TIOException {
+    public void write(int oneChar) throws IOException {
         char[] array = { (char) oneChar };
         write(array, 0, array.length);
     }
 
     @Override
-    public void write(String str, int offset, int count) throws TIOException {
+    public void write(String str, int offset, int count) throws IOException {
         if (str == null) {
             throw new NullPointerException();
         }

classlib/src/main/java/org/teavm/classlib/java/io/TPrintStream.java

@@ -15,13 +15,17 @@
  */
 package org.teavm.classlib.java.io;
 
+import java.io.IOException;
 import org.teavm.classlib.java.lang.TMath;
 import org.teavm.classlib.java.lang.TObject;
-import org.teavm.classlib.java.lang.TString;
 import org.teavm.classlib.java.lang.TStringBuilder;
 import org.teavm.classlib.java.nio.TByteBuffer;
 import org.teavm.classlib.java.nio.TCharBuffer;
-import org.teavm.classlib.java.nio.charset.*;
+import org.teavm.classlib.java.nio.charset.TCharset;
+import org.teavm.classlib.java.nio.charset.TCharsetEncoder;
+import org.teavm.classlib.java.nio.charset.TCodingErrorAction;
+import org.teavm.classlib.java.nio.charset.TIllegalCharsetNameException;
+import org.teavm.classlib.java.nio.charset.TUnsupportedCharsetException;
 import org.teavm.classlib.java.nio.charset.impl.TUTF8Charset;
 
 public class TPrintStream extends TFilterOutputStream {
@@ -31,7 +35,7 @@ public class TPrintStream extends TFilterOutputStream {
     private char[] buffer = new char[32];
     private TCharset charset;
 
-    public TPrintStream(TOutputStream out, boolean autoFlush, TString encoding) throws TUnsupportedEncodingException {
+    public TPrintStream(TOutputStream out, boolean autoFlush, String encoding) throws TUnsupportedEncodingException {
         super(out);
         this.autoFlush = autoFlush;
         try {
@@ -71,7 +75,7 @@ public class TPrintStream extends TFilterOutputStream {
         }
         try {
             out.write(b);
-        } catch (TIOException e) {
+        } catch (IOException e) {
             errorState = true;
         }
         if (autoFlush && !errorState) {
@@ -86,19 +90,19 @@ public class TPrintStream extends TFilterOutputStream {
         }
         try {
             out.write(b, off, len);
-        } catch (TIOException e) {
+        } catch (IOException e) {
             errorState = true;
         }
     }
 
     @Override
-    public void close() throws TIOException {
+    public void close() {
         if (!checkError()) {
             return;
         }
         try {
             out.close();
-        } catch (TIOException e) {
+        } catch (IOException e) {
             errorState = true;
         } finally {
             out = null;
@@ -106,13 +110,13 @@ public class TPrintStream extends TFilterOutputStream {
     }
 
     @Override
-    public void flush() throws TIOException {
+    public void flush() {
         if (!check()) {
             return;
         }
         try {
             out.flush();
-        } catch (TIOException e) {
+        } catch (IOException e) {
             errorState = true;
         }
     }
@@ -173,7 +177,7 @@ public class TPrintStream extends TFilterOutputStream {
         printSB();
     }
 
-    public void print(TString s) {
+    public void print(String s) {
         sb.append(s);
         printSB();
     }
@@ -198,7 +202,7 @@ public class TPrintStream extends TFilterOutputStream {
         printSB();
     }
 
-    public void println(TString s) {
+    public void println(String s) {
         sb.append(s).append('\n');
         printSB();
     }

classlib/src/main/java/org/teavm/classlib/java/io/TPushbackInputStream.java

@@ -15,8 +15,8 @@
  */
 package org.teavm.classlib.java.io;
 
+import java.io.IOException;
 import org.teavm.classlib.java.lang.TArrayIndexOutOfBoundsException;
-import org.teavm.classlib.java.lang.TString;
 
 public class TPushbackInputStream extends TFilterInputStream {
     protected byte[] buf;
@@ -38,15 +38,15 @@ public class TPushbackInputStream extends TFilterInputStream {
     }
 
     @Override
-    public int available() throws TIOException {
+    public int available() throws IOException {
         if (buf == null) {
-            throw new TIOException();
+            throw new IOException();
         }
         return buf.length - pos + in.available();
     }
 
     @Override
-    public void close() throws TIOException {
+    public void close() throws IOException {
         if (in != null) {
             in.close();
             in = null;
@@ -60,9 +60,9 @@ public class TPushbackInputStream extends TFilterInputStream {
     }
 
     @Override
-    public int read() throws TIOException {
+    public int read() throws IOException {
         if (buf == null) {
-            throw new TIOException();
+            throw new IOException();
         }
         // Is there a pushback byte available?
         if (pos < buf.length) {
@@ -74,16 +74,16 @@ public class TPushbackInputStream extends TFilterInputStream {
     }
 
     @Override
-    public int read(byte[] buffer, int offset, int length) throws TIOException {
+    public int read(byte[] buffer, int offset, int length) throws IOException {
         if (buf == null) {
-            throw new TIOException(TString.wrap("Stream is closed"));
+            throw new IOException("Stream is closed");
         }
         // Force buffer null check first!
         if (offset > buffer.length || offset < 0) {
-            throw new TArrayIndexOutOfBoundsException(TString.wrap("Offset out of bounds: " + offset));
+            throw new TArrayIndexOutOfBoundsException("Offset out of bounds: " + offset);
         }
         if (length < 0 || length > buffer.length - offset) {
-            throw new TArrayIndexOutOfBoundsException(TString.wrap("Length out of bounds: " + length));
+            throw new TArrayIndexOutOfBoundsException("Length out of bounds: " + length);
         }
 
         int copiedBytes = 0;
@@ -113,9 +113,9 @@ public class TPushbackInputStream extends TFilterInputStream {
     }
 
     @Override
-    public long skip(long count) throws TIOException {
+    public long skip(long count) throws IOException {
         if (in == null) {
-            throw new TIOException();
+            throw new IOException();
         }
         if (count <= 0) {
             return 0;
@@ -131,44 +131,43 @@ public class TPushbackInputStream extends TFilterInputStream {
         return numSkipped;
     }
 
-    public void unread(byte[] buffer) throws TIOException {
+    public void unread(byte[] buffer) throws IOException {
         unread(buffer, 0, buffer.length);
     }
 
-    public void unread(byte[] buffer, int offset, int length) throws TIOException {
+    public void unread(byte[] buffer, int offset, int length) throws IOException {
         if (length > pos) {
-            throw new TIOException(TString.wrap("Pushback buffer full"));
+            throw new IOException("Pushback buffer full");
         }
         if (offset > buffer.length || offset < 0) {
-            throw new TArrayIndexOutOfBoundsException(TString.wrap("Offset out of bounds: " + offset));
+            throw new TArrayIndexOutOfBoundsException("Offset out of bounds: " + offset);
         }
         if (length < 0 || length > buffer.length - offset) {
-            throw new TArrayIndexOutOfBoundsException(TString.wrap("Length out of bounds: " + length));
+            throw new TArrayIndexOutOfBoundsException("Length out of bounds: " + length);
         }
         if (buf == null) {
-            throw new TIOException(TString.wrap("Stream is closed"));
+            throw new IOException("Stream is closed");
         }
         System.arraycopy(buffer, offset, buf, pos - length, length);
         pos = pos - length;
     }
 
-    public void unread(int oneByte) throws TIOException {
+    public void unread(int oneByte) throws IOException {
         if (buf == null) {
-            throw new TIOException();
+            throw new IOException();
         }
         if (pos == 0) {
-            throw new TIOException();
+            throw new IOException();
         }
         buf[--pos] = (byte) oneByte;
     }
 
     @Override
     public void mark(int readlimit) {
-        return;
     }
 
     @Override
-    public void reset() throws TIOException {
+    public void reset() throws IOException {
-        throw new TIOException();
+        throw new IOException();
     }
 }

classlib/src/main/java/org/teavm/classlib/java/io/TRandomAccessFile.java

@@ -456,7 +456,7 @@ public class TRandomAccessFile implements DataInput, DataOutput, Closeable {
         return new String(out, 0, s);
     }
 
-    static int writeShortToBuffer(int val, byte[] buffer, int offset) throws TIOException {
+    static int writeShortToBuffer(int val, byte[] buffer, int offset) throws IOException {
         buffer[offset++] = (byte) (val >> 8);
         buffer[offset++] = (byte) val;
         return offset;

classlib/src/main/java/org/teavm/classlib/java/io/TReader.java

@@ -15,6 +15,7 @@
  */
 package org.teavm.classlib.java.io;
 
+import java.io.IOException;
 import org.teavm.classlib.java.lang.TMath;
 import org.teavm.classlib.java.lang.TObject;
 
@@ -29,18 +30,18 @@ public abstract class TReader implements TCloseable {
         this.lock = lock;
     }
 
-    public int read() throws TIOException {
+    public int read() throws IOException {
         char[] buf = new char[1];
         return read(buf) >= 0 ? buf[0] : -1;
     }
 
-    public int read(char[] cbuf) throws TIOException {
+    public int read(char[] cbuf) throws IOException {
         return read(cbuf, 0, cbuf.length);
     }
 
-    public abstract int read(char[] cbuf, int off, int len) throws TIOException;
+    public abstract int read(char[] cbuf, int off, int len) throws IOException;
 
-    public long skip(long n) throws TIOException {
+    public long skip(long n) throws IOException {
         char[] buffer = new char[1024];
         long skipped = 0;
         while (skipped < n) {
@@ -53,7 +54,7 @@ public abstract class TReader implements TCloseable {
         return skipped;
     }
 
-    public boolean ready() throws TIOException {
+    public boolean ready() throws IOException {
         return true;
     }
 
@@ -61,11 +62,11 @@ public abstract class TReader implements TCloseable {
         return false;
     }
 
-    public void mark(@SuppressWarnings("unused") int readAheadLimit) throws TIOException {
+    public void mark(@SuppressWarnings("unused") int readAheadLimit) throws IOException {
-        throw new TIOException();
+        throw new IOException();
     }
 
-    public void reset() throws TIOException {
+    public void reset() throws IOException {
-        throw new TIOException();
+        throw new IOException();
     }
 }

classlib/src/main/java/org/teavm/classlib/java/io/TStringReader.java

@@ -15,6 +15,7 @@
  */
 package org.teavm.classlib.java.io;
 
+import java.io.IOException;
 import org.teavm.classlib.java.lang.TIllegalArgumentException;
 import org.teavm.classlib.java.lang.TMath;
 import org.teavm.classlib.java.lang.TNullPointerException;
@@ -33,7 +34,7 @@ public class TStringReader extends TReader {
     }
 
     @Override
-    public int read() throws TIOException {
+    public int read() throws IOException {
         checkOpened();
         if (index >= string.length()) {
             return -1;
@@ -42,7 +43,7 @@ public class TStringReader extends TReader {
     }
 
     @Override
-    public int read(char[] cbuf, int off, int len) throws TIOException {
+    public int read(char[] cbuf, int off, int len) throws IOException {
         checkOpened();
         if (index >= string.length()) {
             return -1;
@@ -55,7 +56,7 @@ public class TStringReader extends TReader {
     }
 
     @Override
-    public long skip(long n) throws TIOException {
+    public long skip(long n) throws IOException {
         checkOpened();
         if (n < 0) {
             n = TMath.max(n, -index);
@@ -67,7 +68,7 @@ public class TStringReader extends TReader {
     }
 
     @Override
-    public boolean ready() throws TIOException {
+    public boolean ready() throws IOException {
         checkOpened();
         return true;
     }
@@ -78,7 +79,7 @@ public class TStringReader extends TReader {
     }
 
     @Override
-    public void mark(int readAheadLimit) throws TIOException {
+    public void mark(int readAheadLimit) throws IOException {
         checkOpened();
         if (readAheadLimit < 0) {
             throw new TIllegalArgumentException();
@@ -87,7 +88,7 @@ public class TStringReader extends TReader {
     }
 
     @Override
-    public void reset() throws TIOException {
+    public void reset() throws IOException {
         checkOpened();
         index = mark;
     }
@@ -97,9 +98,9 @@ public class TStringReader extends TReader {
         string = null;
     }
 
-    private void checkOpened() throws TIOException {
+    private void checkOpened() throws IOException {
         if (string == null) {
-            throw new TIOException();
+            throw new IOException();
         }
     }
 }

classlib/src/main/java/org/teavm/classlib/java/io/TUTFDataFormatException.java

@@ -15,16 +15,16 @@
  */
 package org.teavm.classlib.java.io;
 
-import org.teavm.classlib.java.lang.TString;
+import java.io.IOException;
 
-public class TUTFDataFormatException extends TIOException {
+public class TUTFDataFormatException extends IOException {
     private static final long serialVersionUID = -6383472574962319733L;
 
     public TUTFDataFormatException() {
         super();
     }
 
-    public TUTFDataFormatException(TString message) {
+    public TUTFDataFormatException(String message) {
         super(message);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/io/TUnsupportedEncodingException.java

@@ -15,8 +15,6 @@
  */
 package org.teavm.classlib.java.io;
 
-import org.teavm.classlib.java.lang.TString;
-
 public class TUnsupportedEncodingException extends TIOException {
     private static final long serialVersionUID = 2403781130729330252L;
 
@@ -24,7 +22,7 @@ public class TUnsupportedEncodingException extends TIOException {
         super();
     }
 
-    public TUnsupportedEncodingException(TString message) {
+    public TUnsupportedEncodingException(String message) {
         super(message);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/io/TWriter.java

@@ -15,6 +15,7 @@
  */
 package org.teavm.classlib.java.io;
 
+import java.io.IOException;
 import org.teavm.classlib.java.lang.TAppendable;
 import org.teavm.classlib.java.lang.TCharSequence;
 
@@ -33,13 +34,13 @@ public abstract class TWriter implements TAppendable, TCloseable, TFlushable {
         this.lock = lock;
     }
 
-    public void write(char[] buf) throws TIOException {
+    public void write(char[] buf) throws IOException {
         write(buf, 0, buf.length);
     }
 
-    public abstract void write(char[] buf, int offset, int count) throws TIOException;
+    public abstract void write(char[] buf, int offset, int count) throws IOException;
 
-    public void write(int oneChar) throws TIOException {
+    public void write(int oneChar) throws IOException {
         synchronized (lock) {
             char[] oneCharArray = new char[1];
             oneCharArray[0] = (char) oneChar;
@@ -47,11 +48,11 @@ public abstract class TWriter implements TAppendable, TCloseable, TFlushable {
         }
     }
 
-    public void write(String str) throws TIOException {
+    public void write(String str) throws IOException {
         write(str, 0, str.length());
     }
 
-    public void write(String str, int offset, int count) throws TIOException {
+    public void write(String str, int offset, int count) throws IOException {
         if (count < 0) {
             throw new StringIndexOutOfBoundsException();
         }
@@ -63,19 +64,19 @@ public abstract class TWriter implements TAppendable, TCloseable, TFlushable {
     }
 
     @Override
-    public TWriter append(char c) throws TIOException {
+    public TWriter append(char c) throws IOException {
         write(c);
         return this;
     }
 
     @Override
-    public TWriter append(TCharSequence csq) throws TIOException {
+    public TWriter append(TCharSequence csq) throws IOException {
         write(csq != null ? csq.toString() : "null");
         return this;
     }
 
     @Override
-    public TWriter append(TCharSequence csq, int start, int end) throws TIOException {
+    public TWriter append(TCharSequence csq, int start, int end) throws IOException {
         write(csq != null ? csq.subSequence(start, end).toString() : "null");
         return this;
     }

classlib/src/main/java/org/teavm/classlib/java/lang/TAbstractStringBuilder.java

@@ -56,16 +56,16 @@ class TAbstractStringBuilder extends TObject implements TSerializable, TCharSequ
         length = value.length();
     }
 
-    protected TAbstractStringBuilder append(TString string) {
+    protected TAbstractStringBuilder append(String string) {
         return insert(length, string);
     }
 
-    protected TAbstractStringBuilder insert(int index, TString string) {
+    protected TAbstractStringBuilder insert(int index, String string) {
         if (index < 0 || index > length) {
             throw new TStringIndexOutOfBoundsException();
         }
         if (string == null) {
-            string = TString.wrap("null");
+            string = "null";
         } else if (string.isEmpty()) {
             return this;
         }
@@ -502,7 +502,7 @@ class TAbstractStringBuilder extends TObject implements TSerializable, TCharSequ
     }
 
     protected TAbstractStringBuilder insert(int index, TObject obj) {
-        return insert(index, TString.wrap(obj != null ? obj.toString() : "null"));
+        return insert(index, obj != null ? obj.toString() : "null");
     }
 
     protected TAbstractStringBuilder append(boolean b) {
@@ -510,7 +510,7 @@ class TAbstractStringBuilder extends TObject implements TSerializable, TCharSequ
     }
 
     protected TAbstractStringBuilder insert(int index, boolean b) {
-        return insert(index, b ? TString.wrap("true") : TString.wrap("false"));
+        return insert(index, b ? "true" : "false");
     }
 
     public void ensureCapacity(int capacity) {
@@ -606,7 +606,7 @@ class TAbstractStringBuilder extends TObject implements TSerializable, TCharSequ
 
     public void getChars(int srcBegin, int srcEnd, char[] dst, int dstBegin) {
         if (srcBegin > srcEnd) {
-            throw new TIndexOutOfBoundsException(TString.wrap("Index out of bounds"));
+            throw new IndexOutOfBoundsException("Index out of bounds");
         }
         while (srcBegin < srcEnd) {
             dst[dstBegin++] = buffer[srcBegin++];

classlib/src/main/java/org/teavm/classlib/java/lang/TAppendable.java

@@ -15,12 +15,12 @@
  */
 package org.teavm.classlib.java.lang;
 
-import org.teavm.classlib.java.io.TIOException;
+import java.io.IOException;
 
 public interface TAppendable {
-    TAppendable append(TCharSequence csq) throws TIOException;
+    TAppendable append(TCharSequence csq) throws IOException;
 
-    TAppendable append(TCharSequence csq, int start, int end) throws TIOException;
+    TAppendable append(TCharSequence csq, int start, int end) throws IOException;
 
-    TAppendable append(char c) throws TIOException;
+    TAppendable append(char c) throws IOException;
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TArithmeticException.java

@@ -22,7 +22,7 @@ public class TArithmeticException extends TRuntimeException {
         super();
     }
 
-    public TArithmeticException(TString message) {
+    public TArithmeticException(String message) {
         super(message);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TArrayIndexOutOfBoundsException.java

@@ -22,11 +22,11 @@ public class TArrayIndexOutOfBoundsException extends TIndexOutOfBoundsException
         super();
     }
 
-    public TArrayIndexOutOfBoundsException(TString message) {
+    public TArrayIndexOutOfBoundsException(String message) {
         super(message);
     }
 
     public TArrayIndexOutOfBoundsException(int index) {
-        super(TString.wrap(Integer.toString(index)));
+        super(Integer.toString(index));
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TArrayStoreException.java

@@ -22,7 +22,7 @@ public class TArrayStoreException extends TRuntimeException {
         super();
     }
 
-    public TArrayStoreException(TString message) {
+    public TArrayStoreException(String message) {
         super(message);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TAssertionError.java

@@ -22,11 +22,11 @@ public class TAssertionError extends TError {
         super();
     }
 
-    public TAssertionError(TString message, TThrowable cause) {
+    public TAssertionError(String message, TThrowable cause) {
         super(message, cause);
     }
 
-    public TAssertionError(TObject message) {
+    public TAssertionError(Object message) {
         super(TString.valueOf(message));
     }
 

classlib/src/main/java/org/teavm/classlib/java/lang/TAutoCloseable.java

@@ -16,5 +16,5 @@
 package org.teavm.classlib.java.lang;
 
 public interface TAutoCloseable {
-    void close() throws TException;
+    void close() throws Exception;
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TBoolean.java

@@ -27,7 +27,7 @@ public class TBoolean extends TObject implements TSerializable, TComparable<TBoo
         this.value = value;
     }
 
-    public TBoolean(TString value) {
+    public TBoolean(String value) {
         this.value = parseBoolean(value);
     }
 
@@ -49,8 +49,8 @@ public class TBoolean extends TObject implements TSerializable, TComparable<TBoo
         return 0;
     }
 
-    public static boolean parseBoolean(TString s) {
+    public static boolean parseBoolean(String s) {
-        return s != null && s.toLowerCase().equals(TString.wrap("true"));
+        return s != null && s.toLowerCase().equals("true");
     }
 
     public boolean booleanValue() {
@@ -61,7 +61,7 @@ public class TBoolean extends TObject implements TSerializable, TComparable<TBoo
         return value ? TRUE : FALSE;
     }
 
-    public static TBoolean valueOf(TString value) {
+    public static TBoolean valueOf(String value) {
         return valueOf(parseBoolean(value));
     }
 
@@ -87,8 +87,8 @@ public class TBoolean extends TObject implements TSerializable, TComparable<TBoo
         return obj instanceof TBoolean && ((TBoolean) obj).value == value;
     }
 
-    public static boolean getBoolean(TString key) {
+    public static boolean getBoolean(String key) {
-        String stringValue = key != null ? TSystem.getProperty((String) (Object) key) : null;
+        String stringValue = key != null ? TSystem.getProperty(key) : null;
-        return stringValue != null && valueOf(TString.wrap(stringValue)).booleanValue();
+        return stringValue != null && valueOf(stringValue).booleanValue();
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TByte.java

@@ -26,7 +26,7 @@ public class TByte extends TNumber implements TComparable<TByte> {
         this.value = value;
     }
 
-    public TByte(TString value) {
+    public TByte(String value) {
         this.value = parseByte(value, 10);
     }
 
@@ -88,11 +88,11 @@ public class TByte extends TNumber implements TComparable<TByte> {
         return compare(value, other.value);
     }
 
-    public static byte parseByte(TString s) throws TNumberFormatException {
+    public static byte parseByte(String s) throws TNumberFormatException {
         return parseByte(s, 10);
     }
 
-    public static byte parseByte(TString s, int radix) throws TNumberFormatException {
+    public static byte parseByte(String s, int radix) throws TNumberFormatException {
         int value = TInteger.parseInt(s, radix);
         if (value < MIN_VALUE || value >= MAX_VALUE) {
             throw new TNumberFormatException();
@@ -100,15 +100,15 @@ public class TByte extends TNumber implements TComparable<TByte> {
         return (byte) value;
     }
 
-    public static TByte valueOf(TString s, int radix) throws TNumberFormatException {
+    public static TByte valueOf(String s, int radix) throws TNumberFormatException {
         return valueOf(parseByte(s, radix));
     }
 
-    public static TByte valueOf(TString s) throws TNumberFormatException {
+    public static TByte valueOf(String s) throws TNumberFormatException {
         return valueOf(parseByte(s));
     }
 
-    public static TByte decode(TString nm) throws TNumberFormatException {
+    public static TByte decode(String nm) throws TNumberFormatException {
         TInteger value = TInteger.decode(nm);
         if (value.intValue() < MIN_VALUE || value.intValue() >= MAX_VALUE) {
             throw new TNumberFormatException();

classlib/src/main/java/org/teavm/classlib/java/lang/TClass.java

@@ -53,8 +53,8 @@ import org.teavm.runtime.RuntimeClass;
 import org.teavm.runtime.RuntimeObject;
 
 public class TClass<T> extends TObject implements TAnnotatedElement {
-    TString name;
+    String name;
-    TString simpleName;
+    String simpleName;
     private PlatformClass platformClass;
     private TAnnotation[] annotationsCache;
     private Map<TClass<?>, TAnnotation> annotationsByType;
@@ -105,22 +105,22 @@ public class TClass<T> extends TObject implements TAnnotatedElement {
     }
 
     @Unmanaged
-    public TString getName() {
+    public String getName() {
         if (PlatformDetector.isLowLevel()) {
-            return TString.wrap(Platform.getName(platformClass));
+            return Platform.getName(platformClass);
         } else {
             if (name == null) {
-                name = TString.wrap(Platform.getName(platformClass));
+                name = Platform.getName(platformClass);
             }
             return name;
         }
     }
 
-    public TString getSimpleName() {
+    public String getSimpleName() {
-        TString simpleName = getSimpleNameCache();
+        String simpleName = getSimpleNameCache();
         if (simpleName == null) {
             if (isArray()) {
-                simpleName = getComponentType().getSimpleName().concat(TString.wrap("[]"));
+                simpleName = getComponentType().getSimpleName() + "[]";
                 setSimpleNameCache(simpleName);
                 return simpleName;
             }
@@ -137,14 +137,14 @@ public class TClass<T> extends TObject implements TAnnotatedElement {
                     name = name.substring(lastDot + 1);
                 }
             }
-            simpleName = TString.wrap(name);
+            simpleName = name;
             setSimpleNameCache(simpleName);
         }
         return simpleName;
     }
 
     @DelegateTo("getSimpleNameCacheLowLevel")
-    private TString getSimpleNameCache() {
+    private String getSimpleNameCache() {
         return simpleName;
     }
 
@@ -154,7 +154,7 @@ public class TClass<T> extends TObject implements TAnnotatedElement {
         return Address.ofObject(this).<RuntimeClass>toStructure().simpleName;
     }
 
-    private void setSimpleNameCache(TString value) {
+    private void setSimpleNameCache(String value) {
         simpleName = value;
     }
 
@@ -559,8 +559,7 @@ public class TClass<T> extends TObject implements TAnnotatedElement {
     @SuppressWarnings("unchecked")
     public T cast(TObject obj) {
         if (obj != null && !isAssignableFrom((TClass<?>) (Object) obj.getClass())) {
-            throw new TClassCastException(TString.wrap(obj.getClass().getName()
+            throw new TClassCastException(obj.getClass().getName() + " is not subtype of " + name);
-                    + " is not subtype of " + name));
         }
         return (T) obj;
     }

classlib/src/main/java/org/teavm/classlib/java/lang/TClassCastException.java

@@ -22,7 +22,7 @@ public class TClassCastException extends TRuntimeException {
         super();
     }
 
-    public TClassCastException(TString message) {
+    public TClassCastException(String message) {
         super(message);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TClassNotFoundException.java

@@ -22,11 +22,11 @@ public class TClassNotFoundException extends TReflectiveOperationException {
         super();
     }
 
-    public TClassNotFoundException(TString message, TThrowable cause) {
+    public TClassNotFoundException(String message, TThrowable cause) {
         super(message, cause);
     }
 
-    public TClassNotFoundException(TString message) {
+    public TClassNotFoundException(String message) {
         super(message);
     }
 

classlib/src/main/java/org/teavm/classlib/java/lang/TCloneNotSupportedException.java

@@ -22,7 +22,7 @@ public class TCloneNotSupportedException extends TException {
         super();
     }
 
-    public TCloneNotSupportedException(TString message) {
+    public TCloneNotSupportedException(String message) {
         super(message);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TConsoleInputStream.java

@@ -15,18 +15,18 @@
  */
 package org.teavm.classlib.java.lang;
 
+import java.io.IOException;
 import org.teavm.classlib.java.io.TEOFException;
-import org.teavm.classlib.java.io.TIOException;
 import org.teavm.classlib.java.io.TInputStream;
 
 class TConsoleInputStream extends TInputStream {
     @Override
-    public int read(byte[] b) throws TIOException {
+    public int read(byte[] b) throws IOException {
         throw new TEOFException();
     }
 
     @Override
-    public int read() throws TIOException {
+    public int read() throws IOException {
         throw new TEOFException();
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TConsoleOutputStreamStderr.java

@@ -15,7 +15,7 @@
  */
 package org.teavm.classlib.java.lang;
 
-import org.teavm.classlib.java.io.TIOException;
+import java.io.IOException;
 import org.teavm.classlib.java.io.TOutputStream;
 import org.teavm.interop.DelegateTo;
 import org.teavm.interop.Import;
@@ -24,7 +24,7 @@ import org.teavm.jso.JSBody;
 class TConsoleOutputStreamStderr extends TOutputStream {
     @Override
     @DelegateTo("writeLowLevel")
-    public void write(int b) throws TIOException {
+    public void write(int b) throws IOException {
         writeJs(b);
     }
 

classlib/src/main/java/org/teavm/classlib/java/lang/TConsoleOutputStreamStdout.java

@@ -15,7 +15,7 @@
  */
 package org.teavm.classlib.java.lang;
 
-import org.teavm.classlib.java.io.TIOException;
+import java.io.IOException;
 import org.teavm.classlib.java.io.TOutputStream;
 import org.teavm.interop.DelegateTo;
 import org.teavm.jso.JSBody;
@@ -23,7 +23,7 @@ import org.teavm.jso.JSBody;
 class TConsoleOutputStreamStdout extends TOutputStream {
     @Override
     @DelegateTo("writeLowLevel")
-    public void write(int b) throws TIOException {
+    public void write(int b) throws IOException {
         writeJs(b);
     }
 

classlib/src/main/java/org/teavm/classlib/java/lang/TDouble.java

@@ -251,11 +251,11 @@ public class TDouble extends TNumber implements TComparable<TDouble> {
     @Import(name = "teavm_reinterpretLongToDouble")
     public static native double longBitsToDouble(long bits);
 
-    public static TString toHexString(double d) {
+    public static String toHexString(double d) {
         if (isNaN(d)) {
-            return TString.wrap("NaN");
+            return "NaN";
         } else if (isInfinite(d)) {
-            return d > 0 ? TString.wrap("Infinity") : TString.wrap("-Infinity");
+            return d > 0 ? "Infinity" : "-Infinity";
         }
         char[] buffer = new char[30];
         int sz = 0;
@@ -312,6 +312,6 @@ public class TDouble extends TNumber implements TComparable<TDouble> {
             buffer[sz++] = '0';
         }
 
-        return new TString(buffer, 0, sz);
+        return new String(buffer, 0, sz);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TEnum.java

@@ -64,8 +64,8 @@ public abstract class TEnum<E extends TEnum<E>> extends TObject implements TComp
     @Override
     public final int compareTo(E o) {
         if (o.getDeclaringClass() != getDeclaringClass()) {
-            throw new TIllegalArgumentException(TString.wrap("Can't compare "
+            throw new TIllegalArgumentException("Can't compare "
-                    + getDeclaringClass().getName().toString() + " to " + o.getDeclaringClass().getName().toString()));
+                    + getDeclaringClass().getName() + " to " + o.getDeclaringClass().getName());
         }
         return TInteger.compare(ordinal, o.ordinal());
     }
@@ -74,14 +74,13 @@ public abstract class TEnum<E extends TEnum<E>> extends TObject implements TComp
         // TODO: speed-up this method, use caching
         T[] constants = enumType.getEnumConstants();
         if (constants == null) {
-            throw new TIllegalArgumentException(TString.wrap("Class does not represent enum: " + enumType.getName()));
+            throw new TIllegalArgumentException("Class does not represent enum: " + enumType.getName());
         }
         for (T constant : constants) {
             if (constant.name().equals(name)) {
                 return constant;
             }
         }
-        throw new TIllegalArgumentException(TString.wrap("Enum " + enumType.getName() + " does not have the " + name
+        throw new TIllegalArgumentException("Enum " + enumType.getName() + " does not have the " + name + "constant");
-                + "constant"));
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TError.java

@@ -21,11 +21,11 @@ public class TError extends TThrowable {
     public TError() {
     }
 
-    public TError(TString message, TThrowable cause) {
+    public TError(String message, TThrowable cause) {
         super(message, cause);
     }
 
-    public TError(TString message) {
+    public TError(String message) {
         super(message);
     }
 

classlib/src/main/java/org/teavm/classlib/java/lang/TException.java

@@ -22,11 +22,11 @@ public class TException extends TThrowable {
         super();
     }
 
-    public TException(TString message, TThrowable cause) {
+    public TException(String message, TThrowable cause) {
         super(message, cause);
     }
 
-    public TException(TString message) {
+    public TException(String message) {
         super(message);
     }
 

classlib/src/main/java/org/teavm/classlib/java/lang/TFloat.java

@@ -256,11 +256,11 @@ public class TFloat extends TNumber implements TComparable<TFloat> {
     @Import(name = "teavm_reinterpretIntToFloat")
     public static native float intBitsToFloat(int bits);
 
-    public static TString toHexString(float f) {
+    public static String toHexString(float f) {
         if (isNaN(f)) {
-            return TString.wrap("NaN");
+            return "NaN";
         } else if (isInfinite(f)) {
-            return f > 0 ? TString.wrap("Infinity") : TString.wrap("-Infinity");
+            return f > 0 ? "Infinity" : "-Infinity";
         }
         char[] buffer = new char[18];
         int sz = 0;
@@ -317,6 +317,6 @@ public class TFloat extends TNumber implements TComparable<TFloat> {
             buffer[sz++] = '0';
         }
 
-        return new TString(buffer, 0, sz);
+        return new String(buffer, 0, sz);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TIllegalArgumentException.java

@@ -22,11 +22,11 @@ public class TIllegalArgumentException extends TRuntimeException {
         super();
     }
 
-    public TIllegalArgumentException(TString message, TThrowable cause) {
+    public TIllegalArgumentException(String message, TThrowable cause) {
         super(message, cause);
     }
 
-    public TIllegalArgumentException(TString message) {
+    public TIllegalArgumentException(String message) {
         super(message);
     }
 

classlib/src/main/java/org/teavm/classlib/java/lang/TIllegalMonitorStateException.java

@@ -22,7 +22,7 @@ public class TIllegalMonitorStateException extends TRuntimeException {
         super();
     }
 
-    public TIllegalMonitorStateException(TString message) {
+    public TIllegalMonitorStateException(String message) {
         super(message);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TIllegalStateException.java

@@ -22,11 +22,11 @@ public class TIllegalStateException extends TException {
         super();
     }
 
-    public TIllegalStateException(TString message, TThrowable cause) {
+    public TIllegalStateException(String message, TThrowable cause) {
         super(message, cause);
     }
 
-    public TIllegalStateException(TString message) {
+    public TIllegalStateException(String message) {
         super(message);
     }
 

classlib/src/main/java/org/teavm/classlib/java/lang/TIncompatibleClassChangeError.java

@@ -22,7 +22,7 @@ public class TIncompatibleClassChangeError extends TLinkageError {
         super();
     }
 
-    public TIncompatibleClassChangeError(TString message) {
+    public TIncompatibleClassChangeError(String message) {
         super(message);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TIndexOutOfBoundsException.java

@@ -22,7 +22,7 @@ public class TIndexOutOfBoundsException extends TRuntimeException {
         super();
     }
 
-    public TIndexOutOfBoundsException(TString message) {
+    public TIndexOutOfBoundsException(String message) {
         super(message);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TInteger.java

@@ -30,7 +30,7 @@ public class TInteger extends TNumber implements TComparable<TInteger> {
         this.value = value;
     }
 
-    public TInteger(TString s) throws NumberFormatException {
+    public TInteger(String s) throws NumberFormatException {
         this(parseInt(s));
     }
 
@@ -57,12 +57,12 @@ public class TInteger extends TNumber implements TComparable<TInteger> {
         return toString(i, 10);
     }
 
-    public static int parseInt(TString s, int radix) throws TNumberFormatException {
+    public static int parseInt(String s, int radix) throws TNumberFormatException {
         if (radix < TCharacter.MIN_RADIX || radix > TCharacter.MAX_RADIX) {
-            throw new TNumberFormatException(TString.wrap("Illegal radix: " + radix));
+            throw new TNumberFormatException("Illegal radix: " + radix);
         }
         if (s == null || s.isEmpty()) {
-            throw new TNumberFormatException(TString.wrap("String is null or empty"));
+            throw new TNumberFormatException("String is null or empty");
         }
         boolean negative = false;
         int index = 0;
@@ -82,32 +82,32 @@ public class TInteger extends TNumber implements TComparable<TInteger> {
         while (index < s.length()) {
             int digit = TCharacter.getNumericValue(s.charAt(index++));
             if (digit < 0) {
-                throw new TNumberFormatException(TString.wrap("String contains invalid digits: " + s));
+                throw new TNumberFormatException("String contains invalid digits: " + s);
             }
             if (digit >= radix) {
-                throw new TNumberFormatException(TString.wrap("String contains digits out of radix " + radix
+                throw new TNumberFormatException("String contains digits out of radix " + radix
-                        + ": " + s));
+                        + ": " + s);
             }
             value = radix * value + digit;
             if (value < 0) {
                 if (index == s.length() && value == MIN_VALUE && negative) {
                     return MIN_VALUE;
                 }
-                throw new TNumberFormatException(TString.wrap("The value is too big for int type: " + s));
+                throw new TNumberFormatException("The value is too big for int type: " + s);
             }
         }
         return negative ? -value : value;
     }
 
-    public static int parseInt(TString s) throws TNumberFormatException {
+    public static int parseInt(String s) throws TNumberFormatException {
         return parseInt(s, 10);
     }
 
-    public static TInteger valueOf(TString s, int radix) throws TNumberFormatException {
+    public static TInteger valueOf(String s, int radix) throws TNumberFormatException {
         return valueOf(parseInt(s, radix));
     }
 
-    public static TInteger valueOf(TString s) throws TNumberFormatException {
+    public static TInteger valueOf(String s) throws TNumberFormatException {
         return valueOf(s, 10);
     }
 
@@ -175,7 +175,7 @@ public class TInteger extends TNumber implements TComparable<TInteger> {
     }
 
     public static TInteger getInteger(TString nm, TInteger val) {
-        TString result = nm != null ? TString.wrap(TSystem.getProperty(nm.toString())) : null;
+        String result = nm != null ? TSystem.getProperty(nm.toString()) : null;
         try {
             return result != null ? TInteger.valueOf(result) : val;
         } catch (NumberFormatException e) {
@@ -183,9 +183,9 @@ public class TInteger extends TNumber implements TComparable<TInteger> {
         }
     }
 
-    public static TInteger decode(TString nm) throws TNumberFormatException {
+    public static TInteger decode(String nm) throws TNumberFormatException {
         if (nm == null || nm.isEmpty()) {
-            throw new TNumberFormatException(TString.wrap("Can't parse empty or null string"));
+            throw new TNumberFormatException("Can't parse empty or null string");
         }
         int index = 0;
         boolean negaive = false;
@@ -196,7 +196,7 @@ public class TInteger extends TNumber implements TComparable<TInteger> {
             negaive = true;
         }
         if (index >= nm.length()) {
-            throw new TNumberFormatException(TString.wrap("The string does not represent a number"));
+            throw new TNumberFormatException("The string does not represent a number");
         }
         int radix = 10;
         if (nm.charAt(index) == '#') {
@@ -215,20 +215,20 @@ public class TInteger extends TNumber implements TComparable<TInteger> {
             }
         }
         if (index >= nm.length()) {
-            throw new TNumberFormatException(TString.wrap("The string does not represent a number"));
+            throw new TNumberFormatException("The string does not represent a number");
         }
         int value = 0;
         while (index < nm.length()) {
             int digit = decodeDigit(nm.charAt(index++));
             if (digit >= radix) {
-                throw new TNumberFormatException(TString.wrap("The string does not represent a number"));
+                throw new TNumberFormatException("The string does not represent a number");
             }
             value = value * radix + digit;
             if (value < 0) {
                 if (negaive && value == MIN_VALUE && index == nm.length()) {
                     return TInteger.valueOf(MIN_VALUE);
                 }
-                throw new TNumberFormatException(TString.wrap("The string represents a too big number"));
+                throw new TNumberFormatException("The string represents a too big number");
             }
         }
         return TInteger.valueOf(negaive ? -value : value);

classlib/src/main/java/org/teavm/classlib/java/lang/TInternalError.java

@@ -20,11 +20,11 @@ public class TInternalError extends TVirtualMachineError {
     public TInternalError() {
     }
 
-    public TInternalError(TString message) {
+    public TInternalError(String message) {
         super(message);
     }
 
-    public TInternalError(TString message, TThrowable cause) {
+    public TInternalError(String message, TThrowable cause) {
         super(message, cause);
     }
 

classlib/src/main/java/org/teavm/classlib/java/lang/TLinkageError.java

@@ -22,11 +22,11 @@ public class TLinkageError extends TError {
         super();
     }
 
-    public TLinkageError(TString message, TThrowable cause) {
+    public TLinkageError(String message, TThrowable cause) {
         super(message, cause);
     }
 
-    public TLinkageError(TString message) {
+    public TLinkageError(String message) {
         super(message);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TLong.java

@@ -29,7 +29,7 @@ public class TLong extends TNumber implements TComparable<TLong> {
         this.value = value;
     }
 
-    public TLong(TString value) throws TNumberFormatException {
+    public TLong(String value) throws TNumberFormatException {
         this(parseLong(value));
     }
 
@@ -37,12 +37,12 @@ public class TLong extends TNumber implements TComparable<TLong> {
         return new TLong(value);
     }
 
-    public static long parseLong(TString s, int radix) throws TNumberFormatException {
+    public static long parseLong(String s, int radix) throws TNumberFormatException {
         if (radix < TCharacter.MIN_RADIX || radix > TCharacter.MAX_RADIX) {
-            throw new TNumberFormatException(TString.wrap("Illegal radix: " + radix));
+            throw new TNumberFormatException("Illegal radix: " + radix);
         }
         if (s == null || s.isEmpty()) {
-            throw new TNumberFormatException(TString.wrap("String is null or empty"));
+            throw new TNumberFormatException("String is null or empty");
         }
         boolean negative = false;
         int index = 0;
@@ -59,38 +59,38 @@ public class TLong extends TNumber implements TComparable<TLong> {
         while (index < s.length()) {
             int digit = TCharacter.getNumericValue(s.charAt(index++));
             if (digit < 0) {
-                throw new TNumberFormatException(TString.wrap("String contains invalid digits: " + s));
+                throw new TNumberFormatException("String contains invalid digits: " + s);
             }
             if (digit >= radix) {
-                throw new TNumberFormatException(TString.wrap("String contains digits out of radix " + radix
+                throw new TNumberFormatException("String contains digits out of radix " + radix
-                        + ": " + s));
+                        + ": " + s);
             }
             value = radix * value + digit;
             if (value < 0) {
                 if (index == s.length() && value == MIN_VALUE && negative) {
                     return MIN_VALUE;
                 }
-                throw new TNumberFormatException(TString.wrap("The value is too big for int type: " + s));
+                throw new TNumberFormatException("The value is too big for int type: " + s);
             }
         }
         return negative ? -value : value;
     }
 
-    public static long parseLong(TString s) throws TNumberFormatException {
+    public static long parseLong(String s) throws TNumberFormatException {
         return parseLong(s, 10);
     }
 
-    public static TLong valueOf(TString s, int radix) throws TNumberFormatException {
+    public static TLong valueOf(String s, int radix) throws TNumberFormatException {
         return valueOf(parseLong(s, radix));
     }
 
-    public static TLong valueOf(TString s) throws TNumberFormatException {
+    public static TLong valueOf(String s) throws TNumberFormatException {
         return valueOf(parseLong(s));
     }
 
     public static TLong decode(TString nm) throws TNumberFormatException {
         if (nm == null || nm.isEmpty()) {
-            throw new TNumberFormatException(TString.wrap("Can't parse empty or null string"));
+            throw new TNumberFormatException("Can't parse empty or null string");
         }
         int index = 0;
         boolean negaive = false;
@@ -101,7 +101,7 @@ public class TLong extends TNumber implements TComparable<TLong> {
             negaive = true;
         }
         if (index >= nm.length()) {
-            throw new TNumberFormatException(TString.wrap("The string does not represent a number"));
+            throw new TNumberFormatException("The string does not represent a number");
         }
         int radix = 10;
         if (nm.charAt(index) == '#') {
@@ -120,20 +120,20 @@ public class TLong extends TNumber implements TComparable<TLong> {
             }
         }
         if (index >= nm.length()) {
-            throw new TNumberFormatException(TString.wrap("The string does not represent a number"));
+            throw new TNumberFormatException("The string does not represent a number");
         }
         long value = 0;
         while (index < nm.length()) {
             int digit = decodeDigit(nm.charAt(index++));
             if (digit >= radix) {
-                throw new TNumberFormatException(TString.wrap("The string does not represent a number"));
+                throw new TNumberFormatException("The string does not represent a number");
             }
             value = value * radix + digit;
             if (value < 0) {
                 if (negaive && value == MIN_VALUE && index == nm.length()) {
                     return TLong.valueOf(MIN_VALUE);
                 }
-                throw new TNumberFormatException(TString.wrap("The string represents a too big number"));
+                throw new TNumberFormatException("The string represents a too big number");
             }
         }
         return TLong.valueOf(negaive ? -value : value);
@@ -219,16 +219,16 @@ public class TLong extends TNumber implements TComparable<TLong> {
         return compare(value, other.value);
     }
 
-    public static TLong getLong(TString nm) {
+    public static TLong getLong(String nm) {
         return getLong(nm, null);
     }
 
-    public static TLong getLong(TString nm, long val) {
+    public static TLong getLong(String nm, long val) {
         return getLong(nm, TLong.valueOf(val));
     }
 
-    public static TLong getLong(TString nm, TLong val) {
+    public static TLong getLong(String nm, TLong val) {
-        TString result = nm != null ? TString.wrap(TSystem.getProperty(nm.toString())) : null;
+        String result = nm != null ? TSystem.getProperty(nm) : null;
         try {
             return result != null ? TLong.valueOf(result) : val;
         } catch (NumberFormatException e) {

classlib/src/main/java/org/teavm/classlib/java/lang/TNegativeArraySizeException.java

@@ -22,7 +22,7 @@ public class TNegativeArraySizeException extends TRuntimeException {
         super();
     }
 
-    public TNegativeArraySizeException(TString message) {
+    public TNegativeArraySizeException(String message) {
         super(message);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TNoClassDefFoundError.java

@@ -22,7 +22,7 @@ public class TNoClassDefFoundError extends TLinkageError {
         super();
     }
 
-    public TNoClassDefFoundError(TString message) {
+    public TNoClassDefFoundError(String message) {
         super(message);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TNoSuchFieldError.java

@@ -22,7 +22,7 @@ public class TNoSuchFieldError extends TIncompatibleClassChangeError {
         super();
     }
 
-    public TNoSuchFieldError(TString message) {
+    public TNoSuchFieldError(String message) {
         super(message);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TNoSuchMethodError.java

@@ -22,7 +22,7 @@ public class TNoSuchMethodError extends TIncompatibleClassChangeError {
         super();
     }
 
-    public TNoSuchMethodError(TString message) {
+    public TNoSuchMethodError(String message) {
         super(message);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TNoSuchMethodException.java

@@ -19,7 +19,7 @@ public class TNoSuchMethodException extends TReflectiveOperationException {
     public TNoSuchMethodException() {
     }
 
-    public TNoSuchMethodException(TString message) {
+    public TNoSuchMethodException(String message) {
         super(message);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TNullPointerException.java

@@ -18,7 +18,7 @@ package org.teavm.classlib.java.lang;
 public class TNullPointerException extends TRuntimeException {
     private static final long serialVersionUID = 2639861320773057190L;
 
-    public TNullPointerException(TString message) {
+    public TNullPointerException(String message) {
         super(message);
     }
 

classlib/src/main/java/org/teavm/classlib/java/lang/TNumberFormatException.java

@@ -22,7 +22,7 @@ public class TNumberFormatException extends TIllegalArgumentException {
         super();
     }
 
-    public TNumberFormatException(TString message) {
+    public TNumberFormatException(String message) {
         super(message);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TObject.java

@@ -23,7 +23,6 @@ import org.teavm.interop.Rename;
 import org.teavm.interop.Structure;
 import org.teavm.interop.Superclass;
 import org.teavm.interop.Sync;
-import org.teavm.interop.Unmanaged;
 import org.teavm.jso.browser.TimerHandler;
 import org.teavm.platform.Platform;
 import org.teavm.platform.PlatformObject;
@@ -392,9 +391,4 @@ public class TObject {
     @Override
     protected void finalize() throws TThrowable {
     }
-
-    @Unmanaged
-    public static TObject wrap(Object obj) {
-        return (TObject) obj;
-    }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TOutOfMemoryError.java

@@ -22,7 +22,7 @@ public class TOutOfMemoryError extends TVirtualMachineError {
         super();
     }
 
-    public TOutOfMemoryError(TString message) {
+    public TOutOfMemoryError(String message) {
         super(message);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TReflectiveOperationException.java

@@ -22,11 +22,11 @@ public class TReflectiveOperationException extends TException {
         super();
     }
 
-    public TReflectiveOperationException(TString message, TThrowable cause) {
+    public TReflectiveOperationException(String message, TThrowable cause) {
         super(message, cause);
     }
 
-    public TReflectiveOperationException(TString message) {
+    public TReflectiveOperationException(String message) {
         super(message);
     }
 

classlib/src/main/java/org/teavm/classlib/java/lang/TRuntimeException.java

@@ -25,11 +25,11 @@ public class TRuntimeException extends TException {
         super();
     }
 
-    public TRuntimeException(TString message, TThrowable cause) {
+    public TRuntimeException(String message, TThrowable cause) {
         super(message, cause);
     }
 
-    public TRuntimeException(TString message) {
+    public TRuntimeException(String message) {
         super(message);
     }
 

classlib/src/main/java/org/teavm/classlib/java/lang/TSecurityException.java

@@ -22,11 +22,11 @@ public class TSecurityException extends TRuntimeException {
         super();
     }
 
-    public TSecurityException(TString message, TThrowable cause) {
+    public TSecurityException(String message, TThrowable cause) {
         super(message, cause);
     }
 
-    public TSecurityException(TString message) {
+    public TSecurityException(String message) {
         super(message);
     }
 

classlib/src/main/java/org/teavm/classlib/java/lang/TShort.java

@@ -26,7 +26,7 @@ public class TShort extends TNumber implements TComparable<TShort> {
         this.value = value;
     }
 
-    public TShort(TString s) throws TNumberFormatException {
+    public TShort(String s) throws TNumberFormatException {
         this(parseShort(s));
     }
 
@@ -87,7 +87,7 @@ public class TShort extends TNumber implements TComparable<TShort> {
         return compare(value, other.value);
     }
 
-    public static short parseShort(TString s, int radix) throws TNumberFormatException {
+    public static short parseShort(String s, int radix) throws TNumberFormatException {
         int value = TInteger.parseInt(s, radix);
         if (value < MIN_VALUE || value > MAX_VALUE) {
             throw new TNumberFormatException();
@@ -95,19 +95,19 @@ public class TShort extends TNumber implements TComparable<TShort> {
         return (short) value;
     }
 
-    public static short parseShort(TString s) throws TNumberFormatException {
+    public static short parseShort(String s) throws TNumberFormatException {
         return parseShort(s, 10);
     }
 
-    public static TShort valueOf(TString s, int radix) throws TNumberFormatException {
+    public static TShort valueOf(String s, int radix) throws TNumberFormatException {
         return valueOf(parseShort(s, radix));
     }
 
-    public static TShort valueOf(TString s) throws TNumberFormatException {
+    public static TShort valueOf(String s) throws TNumberFormatException {
         return valueOf(parseShort(s));
     }
 
-    public static TShort decode(TString s) throws TNumberFormatException {
+    public static TShort decode(String s) throws TNumberFormatException {
         int value = TInteger.decode(s).intValue();
         if (value < MIN_VALUE || value > MAX_VALUE) {
             throw new TNumberFormatException();

classlib/src/main/java/org/teavm/classlib/java/lang/TStackOverflowError.java

@@ -31,17 +31,13 @@
  */
 package org.teavm.classlib.java.lang;
 
-/**
- *
- * @author Sergey Kapralov
- */
 public class TStackOverflowError extends TVirtualMachineError {
     
     public TStackOverflowError() {
         super();
     }
 
-    public TStackOverflowError(TString string) {
+    public TStackOverflowError(String string) {
         super(string);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TStackTraceElement.java

@@ -20,12 +20,12 @@ import org.teavm.classlib.java.io.TSerializable;
 import org.teavm.classlib.java.util.TObjects;
 
 public final class TStackTraceElement extends TObject implements TSerializable {
-    private TString declaringClass;
+    private String declaringClass;
-    private TString methodName;
+    private String methodName;
-    private TString fileName;
+    private String fileName;
     private int lineNumber;
 
-    public TStackTraceElement(TString declaringClass, TString methodName, TString fileName, int lineNumber) {
+    public TStackTraceElement(String declaringClass, String methodName, String fileName, int lineNumber) {
         if (declaringClass == null || methodName == null) {
             throw new TNullPointerException();
         }
@@ -35,15 +35,15 @@ public final class TStackTraceElement extends TObject implements TSerializable {
         this.lineNumber = lineNumber;
     }
 
-    public TString getClassName() {
+    public String getClassName() {
         return declaringClass;
     }
 
-    public TString getMethodName() {
+    public String getMethodName() {
         return methodName;
     }
 
-    public TString getFileName() {
+    public String getFileName() {
         return fileName;
     }
 
@@ -77,15 +77,15 @@ public final class TStackTraceElement extends TObject implements TSerializable {
 
     @Override
     public String toString() {
-        TStringBuilder sb = new TStringBuilder();
+        StringBuilder sb = new StringBuilder();
         int index = declaringClass.lastIndexOf('.');
         sb.append(declaringClass.substring(index + 1)).append('.').append(methodName).append('(');
         if (fileName != null) {
             sb.append(fileName).append(':').append(lineNumber);
         } else {
-            sb.append(TString.wrap("Unknown Source"));
+            sb.append("Unknown Source");
         }
-        sb.append(TString.wrap(")"));
+        sb.append(")");
         return sb.toString();
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TString.java

@@ -30,7 +30,6 @@ import org.teavm.classlib.java.util.THashMap;
 import org.teavm.classlib.java.util.TLocale;
 import org.teavm.classlib.java.util.TMap;
 import org.teavm.classlib.java.util.regex.TPattern;
-import org.teavm.interop.Unmanaged;
 
 public class TString extends TObject implements TSerializable, TComparable<TString>, TCharSequence {
     public static final TComparator<TString> CASE_INSENSITIVE_ORDER = (o1, o2) -> o1.compareToIgnoreCase(o2);
@@ -425,8 +424,8 @@ public class TString extends TObject implements TSerializable, TComparable<TStri
         return false;
     }
 
-    public TString replace(TCharSequence target, TCharSequence replacement) {
+    public String replace(TCharSequence target, TCharSequence replacement) {
-        TStringBuilder sb = new TStringBuilder();
+        StringBuilder sb = new StringBuilder();
         int sz = length() - target.length();
         int i = 0;
         outer:
@@ -441,7 +440,7 @@ public class TString extends TObject implements TSerializable, TComparable<TStri
             i += target.length() - 1;
         }
         sb.append(substring(i));
-        return TString.wrap(sb.toString());
+        return sb.toString();
     }
 
     public TString trim() {
@@ -469,8 +468,8 @@ public class TString extends TObject implements TSerializable, TComparable<TStri
         return array;
     }
 
-    public static TString valueOf(TObject obj) {
+    public static String valueOf(Object obj) {
-        return obj != null ? TString.wrap(obj.toString()) : TString.wrap("null");
+        return obj != null ? obj.toString() : "null";
     }
 
     public static TString valueOf(char[] data) {
@@ -489,28 +488,28 @@ public class TString extends TObject implements TSerializable, TComparable<TStri
         return valueOf(data, offset, count);
     }
 
-    public static TString valueOf(boolean b) {
+    public static String valueOf(boolean b) {
-        return b ? TString.wrap("true") : TString.wrap("false");
+        return b ? "true" : "false";
     }
 
-    public static TString valueOf(char c) {
+    public static String valueOf(char c) {
-        return new TString(new char[] { c });
+        return new String(new char[] { c });
     }
 
-    public static TString valueOf(int i) {
+    public static String valueOf(int i) {
-        return TString.wrap(new TStringBuilder().append(i).toString());
+        return new TStringBuilder().append(i).toString();
     }
 
-    public static TString valueOf(long l) {
+    public static String valueOf(long l) {
-        return TString.wrap(new TStringBuilder().append(l).toString());
+        return new TStringBuilder().append(l).toString();
     }
 
-    public static TString valueOf(float f) {
+    public static String valueOf(float f) {
-        return TString.wrap(new TStringBuilder().append(f).toString());
+        return new TStringBuilder().append(f).toString();
     }
 
-    public static TString valueOf(double d) {
+    public static String valueOf(double d) {
-        return TString.wrap(new TStringBuilder().append(d).toString());
+        return new TStringBuilder().append(d).toString();
     }
 
     @Override
@@ -580,11 +579,6 @@ public class TString extends TObject implements TSerializable, TComparable<TStri
         return hashCode;
     }
 
-    @Unmanaged
-    public static TString wrap(String str) {
-        return (TString) (Object) str;
-    }
-
     public TString toLowerCase() {
         if (isEmpty()) {
             return this;

classlib/src/main/java/org/teavm/classlib/java/lang/TStringBuffer.java

@@ -33,7 +33,7 @@ public class TStringBuffer extends TAbstractStringBuilder implements TAppendable
     }
 
     @Override
-    public TStringBuffer append(TString string) {
+    public TStringBuffer append(String string) {
         super.append(string);
         return this;
     }
@@ -201,7 +201,7 @@ public class TStringBuffer extends TAbstractStringBuilder implements TAppendable
     }
 
     @Override
-    public TStringBuffer insert(int index, TString string) {
+    public TStringBuffer insert(int index, String string) {
         super.insert(index, string);
         return this;
     }

classlib/src/main/java/org/teavm/classlib/java/lang/TStringBuilder.java

@@ -33,7 +33,7 @@ public class TStringBuilder extends TAbstractStringBuilder implements TAppendabl
     }
 
     @Override
-    public TStringBuilder append(TString string) {
+    public TStringBuilder append(String string) {
         super.append(string);
         return this;
     }
@@ -201,7 +201,7 @@ public class TStringBuilder extends TAbstractStringBuilder implements TAppendabl
     }
 
     @Override
-    public TStringBuilder insert(int index, TString string) {
+    public TStringBuilder insert(int index, String string) {
         super.insert(index, string);
         return this;
     }

classlib/src/main/java/org/teavm/classlib/java/lang/TStringIndexOutOfBoundsException.java

@@ -22,12 +22,11 @@ public class TStringIndexOutOfBoundsException extends TIndexOutOfBoundsException
         super();
     }
 
-    public TStringIndexOutOfBoundsException(TString message) {
+    public TStringIndexOutOfBoundsException(String message) {
         super(message);
     }
 
     public TStringIndexOutOfBoundsException(int index) {
-        super(TString.wrap(new TStringBuilder().append(TString.wrap("String index out of bounds: "))
+        super(new TStringBuilder().append("String index out of bounds: ").append(index).toString());
-                .append(index).toString()));
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/TSystem.java

@@ -68,7 +68,7 @@ public final class TSystem extends TObject {
 
     public static void arraycopy(TObject src, int srcPos, TObject dest, int destPos, int length) {
         if (src == null || dest == null) {
-            throw new TNullPointerException(TString.wrap("Either src or dest is null"));
+            throw new TNullPointerException("Either src or dest is null");
         }
         if (srcPos < 0 || destPos < 0 || length < 0 || srcPos + length > TArray.getLength(src)
                 || destPos + length > TArray.getLength(dest)) {

classlib/src/main/java/org/teavm/classlib/java/lang/TThread.java

@@ -21,7 +21,7 @@ import org.teavm.platform.PlatformRunnable;
 import org.teavm.platform.async.AsyncCallback;
 
 public class TThread extends TObject implements TRunnable {
-    private static TThread mainThread = new TThread(TString.wrap("main"));
+    private static TThread mainThread = new TThread("main");
     private static TThread currentThread = mainThread;
     private static long nextId = 1;
     private static int activeCount = 1;
@@ -33,7 +33,7 @@ public class TThread extends TObject implements TRunnable {
     private boolean interruptedFlag;
     public TThreadInterruptHandler interruptHandler;
 
-    private TString name;
+    private String name;
     private boolean alive = true;
     TRunnable target;
 
@@ -41,7 +41,7 @@ public class TThread extends TObject implements TRunnable {
         this(null, null);
     }
 
-    public TThread(TString name) {
+    public TThread(String name) {
         this(null, name);
     }
 
@@ -49,7 +49,7 @@ public class TThread extends TObject implements TRunnable {
         this(target, null);
     }
 
-    public TThread(TRunnable target, TString name) {
+    public TThread(TRunnable target, String name) {
         this.name = name;
         this.target = target;
         id = nextId++;
@@ -94,7 +94,7 @@ public class TThread extends TObject implements TRunnable {
         return currentThread;
     }
 
-    public TString getName() {
+    public String getName() {
         return name;
     }
 

classlib/src/main/java/org/teavm/classlib/java/lang/TThrowable.java

@@ -15,8 +15,8 @@
  */
 package org.teavm.classlib.java.lang;
 
-import org.teavm.classlib.java.io.TPrintStream;
+import java.io.PrintStream;
-import org.teavm.classlib.java.io.TPrintWriter;
+import java.io.PrintWriter;
 import org.teavm.classlib.java.util.TArrays;
 import org.teavm.interop.DelegateTo;
 import org.teavm.interop.Remove;
@@ -27,7 +27,7 @@ import org.teavm.runtime.ExceptionHandling;
 @Superclass("java.lang.Object")
 public class TThrowable extends RuntimeException {
     private static final long serialVersionUID = 2026791432677149320L;
-    private TString message;
+    private String message;
     private TThrowable cause;
     private boolean suppressionEnabled;
     private boolean writableStackTrace;
@@ -36,11 +36,11 @@ public class TThrowable extends RuntimeException {
 
     @SuppressWarnings("unused")
     @Rename("fakeInit")
-    protected TThrowable(TString message, TThrowable cause, boolean enableSuppression, boolean writableStackTrace) {
+    protected TThrowable(String message, TThrowable cause, boolean enableSuppression, boolean writableStackTrace) {
     }
 
     @Rename("<init>")
-    public void init(TString message, TThrowable cause, boolean enableSuppression, boolean writableStackTrace) {
+    public void init(String message, TThrowable cause, boolean enableSuppression, boolean writableStackTrace) {
         if (writableStackTrace) {
             fillInStackTrace();
         }
@@ -62,11 +62,11 @@ public class TThrowable extends RuntimeException {
     }
 
     @Rename("fakeInit")
-    public TThrowable(@SuppressWarnings("unused") TString message) {
+    public TThrowable(@SuppressWarnings("unused") String message) {
     }
 
     @Rename("<init>")
-    private void init(TString message) {
+    private void init(String message) {
         this.suppressionEnabled = true;
         this.writableStackTrace = true;
         fillInStackTrace();
@@ -75,11 +75,11 @@ public class TThrowable extends RuntimeException {
 
     @SuppressWarnings("unused")
     @Rename("fakeInit")
-    public TThrowable(TString message, TThrowable cause) {
+    public TThrowable(String message, TThrowable cause) {
     }
 
     @Rename("<init>")
-    private void init(TString message, TThrowable cause) {
+    private void init(String message, TThrowable cause) {
         this.suppressionEnabled = true;
         this.writableStackTrace = true;
         fillInStackTrace();
@@ -114,13 +114,13 @@ public class TThrowable extends RuntimeException {
     }
 
     @Rename("getMessage")
-    public TString getMessage0() {
+    public String getMessage0() {
         return message;
     }
 
     @Rename("getLocalizedMessage")
-    public TString getLocalizedMessage0() {
+    public String getLocalizedMessage0() {
-        return TString.wrap(getMessage());
+        return getMessage();
     }
 
     @Remove
@@ -132,17 +132,17 @@ public class TThrowable extends RuntimeException {
     }
 
     @Remove
-    public native TClass<?> getClass0();
+    public native Class<?> getClass0();
 
     @Remove
-    public native TString toString0();
+    public native String toString0();
 
     public TThrowable initCause(TThrowable cause) {
         if (this.cause != this && this.cause != null) {
-            throw new TIllegalStateException(TString.wrap("Cause already set"));
+            throw new IllegalStateException("Cause already set");
         }
         if (cause == this) {
-            throw new TIllegalArgumentException(TString.wrap("Circular causation relation"));
+            throw new IllegalArgumentException("Circular causation relation");
         }
         this.cause = cause;
         return this;
@@ -150,38 +150,38 @@ public class TThrowable extends RuntimeException {
 
     @Override
     public void printStackTrace() {
-        printStackTrace(TSystem.err());
+        printStackTrace(System.err);
     }
 
-    public void printStackTrace(TPrintStream stream) {
+    public void printStackTrace(PrintStream stream) {
-        stream.print(TString.wrap(getClass().getName()));
+        stream.print(getClass().getName());
         String message = getMessage();
         if (message != null) {
-            stream.print(TString.wrap(": " + getMessage()));
+            stream.print(": " + getMessage());
         }
         stream.println();
         if (stackTrace != null) {
             for (TStackTraceElement element : stackTrace) {
-                stream.print(TString.wrap("    at "));
+                stream.print("    at ");
                 stream.println(element);
             }
         }
         if (cause != null && cause != this) {
-            stream.print(TString.wrap("Caused by: "));
+            stream.print("Caused by: ");
             cause.printStackTrace(stream);
         }
     }
 
-    public void printStackTrace(TPrintWriter stream) {
+    public void printStackTrace(PrintWriter stream) {
-        stream.println(TString.wrap(getClass().getName() + ": " + getMessage()));
+        stream.println(getClass().getName() + ": " + getMessage());
         if (stackTrace != null) {
             for (TStackTraceElement element : stackTrace) {
-                stream.print(TString.wrap("  at "));
+                stream.print("  at ");
                 stream.println(element);
             }
         }
         if (cause != null && cause != this) {
-            stream.print(TString.wrap("Caused by: "));
+            stream.print("Caused by: ");
             cause.printStackTrace(stream);
         }
     }

classlib/src/main/java/org/teavm/classlib/java/lang/TUnsupportedOperationException.java

@@ -22,11 +22,11 @@ public class TUnsupportedOperationException extends TRuntimeException {
         super();
     }
 
-    public TUnsupportedOperationException(TString message, TThrowable cause) {
+    public TUnsupportedOperationException(String message, TThrowable cause) {
         super(message, cause);
     }
 
-    public TUnsupportedOperationException(TString message) {
+    public TUnsupportedOperationException(String message) {
         super(message);
     }
 

classlib/src/main/java/org/teavm/classlib/java/lang/TVirtualMachineError.java

@@ -22,7 +22,7 @@ public class TVirtualMachineError extends TError {
         super();
     }
 
-    public TVirtualMachineError(TString message) {
+    public TVirtualMachineError(String message) {
         super(message);
     }
 
@@ -30,7 +30,7 @@ public class TVirtualMachineError extends TError {
         super(cause);
     }
 
-    public TVirtualMachineError(TString message, TThrowable cause) {
+    public TVirtualMachineError(String message, TThrowable cause) {
         super(message, cause);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/reflect/TAnnotatedElement.java

@@ -32,7 +32,7 @@ public interface TAnnotatedElement {
 
     TAnnotation[] getDeclaredAnnotations();
 
-    default <T extends TAnnotation> T[] getAnnotationsByType(TClass<T> annotationClass) {
+    default <T extends TAnnotation> T[] getAnnotationsByType(Class<T> annotationClass) {
         List<T> result = new ArrayList<>();
         Object classAsObject = annotationClass;
         for (TAnnotation annot : getAnnotations()) {
@@ -55,7 +55,7 @@ public interface TAnnotatedElement {
         return null;
     }
 
-    default <T extends TAnnotation> T[] getDeclaredAnnotationsByType(TClass<T> annotationClass) {
+    default <T extends TAnnotation> T[] getDeclaredAnnotationsByType(Class<T> annotationClass) {
         List<T> result = new ArrayList<>();
         Object classAsObject = annotationClass;
         for (TAnnotation annot : getDeclaredAnnotations()) {

classlib/src/main/java/org/teavm/classlib/java/lang/reflect/TArray.java

@@ -48,17 +48,17 @@ public final class TArray extends TObject {
     }
 
     @PluggableDependency(ArrayNativeGenerator.class)
-    public static TObject newInstance(TClass<?> componentType, int length) throws TNegativeArraySizeException {
+    public static TObject newInstance(Class<?> componentType, int length) throws TNegativeArraySizeException {
         if (componentType == null) {
             throw new TNullPointerException();
         }
-        if (componentType == TClass.wrap(void.class)) {
+        if (componentType == void.class) {
             throw new TIllegalArgumentException();
         }
         if (length < 0) {
             throw new TNegativeArraySizeException();
         }
-        return newInstanceImpl(componentType.getPlatformClass(), length);
+        return newInstanceImpl(((TClass<?>) (Object) componentType).getPlatformClass(), length);
     }
 
     @GeneratedBy(ArrayNativeGenerator.class)

classlib/src/main/java/org/teavm/classlib/java/lang/reflect/TInvocationTargetException.java

@@ -16,7 +16,6 @@
 package org.teavm.classlib.java.lang.reflect;
 
 import org.teavm.classlib.java.lang.TReflectiveOperationException;
-import org.teavm.classlib.java.lang.TString;
 import org.teavm.classlib.java.lang.TThrowable;
 
 public class TInvocationTargetException extends TReflectiveOperationException {
@@ -27,7 +26,7 @@ public class TInvocationTargetException extends TReflectiveOperationException {
         super(null, target);
     }
 
-    public TInvocationTargetException(TThrowable target, TString s) {
+    public TInvocationTargetException(TThrowable target, String s) {
         super(s, target);
     }
 

classlib/src/main/java/org/teavm/classlib/java/net/TURIEncoderDecoder.java

@@ -21,44 +21,24 @@ import org.teavm.classlib.java.lang.TIllegalArgumentException;
 import org.teavm.classlib.java.lang.TString;
 import org.teavm.classlib.java.lang.TStringBuilder;
 
-/**
- * This class is used to encode a string using the format required by {@code
- * application/x-www-form-urlencoded} MIME content type. It contains helper
- * methods used by the URI class, and performs encoding and decoding in a
- * slightly different way than {@code URLEncoder} and {@code URLDecoder}.
- */
 class TURIEncoderDecoder {
-    static final TString digits = TString.wrap("0123456789ABCDEF");
+    static final String digits = "0123456789ABCDEF";
 
     private TURIEncoderDecoder() {
     }
 
-    /**
+    static void validate(String s, String legal) throws TURISyntaxException {
-     * Validate a string by checking if it contains any characters other than:
-     * 1. letters ('a'..'z', 'A'..'Z') 2. numbers ('0'..'9') 3. characters in
-     * the legalset parameter 4. others (unicode characters that are not in
-     * US-ASCII set, and are not ISO Control or are not ISO Space characters)
-     * <p>
-     * called from {@code URI.Helper.parseURI()} to validate each component
-     *
-     * @param s
-     *            {@code java.lang.String} the string to be validated
-     * @param legal
-     *            {@code java.lang.String} the characters allowed in the String
-     *            s
-     */
-    static void validate(TString s, TString legal) throws TURISyntaxException {
         for (int i = 0; i < s.length();) {
             char ch = s.charAt(i);
             if (ch == '%') {
                 do {
                     if (i + 2 >= s.length()) {
-                        throw new TURISyntaxException(s, TString.wrap(""), i);
+                        throw new TURISyntaxException(s, "", i);
                     }
                     int d1 = TCharacter.digit(s.charAt(i + 1), 16);
                     int d2 = TCharacter.digit(s.charAt(i + 2), 16);
                     if (d1 == -1 || d2 == -1) {
-                        throw new TURISyntaxException(s, TString.wrap(""), i);
+                        throw new TURISyntaxException(s, "", i);
                     }
 
                     i += 3;
@@ -69,7 +49,7 @@ class TURIEncoderDecoder {
             if (!((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z')
                     || (ch >= '0' && ch <= '9') || legal.indexOf(ch) > -1 || (ch > 127
                     && !isSpaceChar(ch) && !TCharacter.isISOControl(ch)))) {
-                throw new TURISyntaxException(s, TString.wrap(""), i); //$NON-NLS-1$
+                throw new TURISyntaxException(s, "", i);
             }
             i++;
         }
@@ -85,38 +65,19 @@ class TURIEncoderDecoder {
         }
     }
 
-    static void validateSimple(TString s, TString legal)
+    static void validateSimple(String s, String legal)
             throws TURISyntaxException {
         for (int i = 0; i < s.length();) {
             char ch = s.charAt(i);
             if (!((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z')
                     || (ch >= '0' && ch <= '9') || legal.indexOf(ch) > -1)) {
-                throw new TURISyntaxException(s, TString.wrap(""), i); //$NON-NLS-1$
+                throw new TURISyntaxException(s, "", i);
             }
             i++;
         }
     }
 
-    /**
+    static String quoteIllegal(String s, String legal) {
-     * All characters except letters ('a'..'z', 'A'..'Z') and numbers ('0'..'9')
-     * and legal characters are converted into their hexidecimal value prepended
-     * by '%'.
-     * <p>
-     * For example: '#' -> %23
-     * Other characters, which are unicode chars that are not US-ASCII, and are
-     * not ISO Control or are not ISO Space chars, are preserved.
-     * <p>
-     * Called from {@code URI.quoteComponent()} (for multiple argument
-     * constructors)
-     *
-     * @param s
-     *            java.lang.String the string to be converted
-     * @param legal
-     *            java.lang.String the characters allowed to be preserved in the
-     *            string s
-     * @return java.lang.String the converted string
-     */
-    static TString quoteIllegal(TString s, TString legal) {
         TStringBuilder buf = new TStringBuilder();
         for (int i = 0; i < s.length(); i++) {
             char ch = s.charAt(i);
@@ -135,23 +96,10 @@ class TURIEncoderDecoder {
                 }
             }
         }
-        return TString.wrap(buf.toString());
+        return buf.toString();
     }
 
-    /**
+    static String encodeOthers(String s) {
-     * Other characters, which are Unicode chars that are not US-ASCII, and are
-     * not ISO Control or are not ISO Space chars are not preserved. They are
-     * converted into their hexidecimal value prepended by '%'.
-     * <p>
-     * For example: Euro currency symbol -> "%E2%82%AC".
-     * <p>
-     * Called from URI.toASCIIString()
-     *
-     * @param s
-     *            java.lang.String the string to be converted
-     * @return java.lang.String the converted string
-     */
-    static TString encodeOthers(TString s) {
         TStringBuilder buf = new TStringBuilder();
         for (int i = 0; i < s.length(); i++) {
             char ch = s.charAt(i);
@@ -166,27 +114,10 @@ class TURIEncoderDecoder {
                 }
             }
         }
-        return TString.wrap(buf.toString());
+        return buf.toString();
     }
 
-    /**
+    static String decode(String s) {
-     * Decodes the string argument which is assumed to be encoded in the {@code
-     * x-www-form-urlencoded} MIME content type using the UTF-8 encoding scheme.
-     * <p>
-     *'%' and two following hex digit characters are converted to the
-     * equivalent byte value. All other characters are passed through
-     * unmodified.
-     * <p>
-     * e.g. "A%20B%20C %24%25" -> "A B C $%"
-     * <p>
-     * Called from URI.getXYZ() methods
-     *
-     * @param s
-     *            java.lang.String The encoded string.
-     * @return java.lang.String The decoded version.
-     */
-    static TString decode(TString s) {
-
         TStringBuilder result = new TStringBuilder();
         TByteArrayOutputStream out = new TByteArrayOutputStream();
         for (int i = 0; i < s.length();) {
@@ -205,13 +136,13 @@ class TURIEncoderDecoder {
                     out.write((byte) ((d1 << 4) + d2));
                     i += 3;
                 } while (i < s.length() && s.charAt(i) == '%');
-                result.append(TString.wrap(out.toString()));
+                result.append(out.toString());
                 continue;
             }
             result.append(c);
             i++;
         }
-        return TString.wrap(result.toString());
+        return result.toString();
     }
 
 }

classlib/src/main/java/org/teavm/classlib/java/net/TURISyntaxException.java

@@ -18,39 +18,13 @@ package org.teavm.classlib.java.net;
 import org.teavm.classlib.java.lang.TException;
 import org.teavm.classlib.java.lang.TIllegalArgumentException;
 import org.teavm.classlib.java.lang.TNullPointerException;
-import org.teavm.classlib.java.lang.TString;
 import org.teavm.interop.Rename;
 
-/**
- * A {@code URISyntaxException} will be thrown if some information could not be parsed
- * while creating a URI.
- */
 public class TURISyntaxException extends TException {
-
+    private String input;
-    private static final long serialVersionUID = 2137979680897488891L;
-
-    private TString input;
-
     private int index;
 
-    /**
+    public TURISyntaxException(String input, String reason, int index) {
-     * Constructs a new {@code URISyntaxException} instance containing the
-     * string that caused the exception, a description of the problem and the
-     * index at which the error occurred.
-     *
-     * @param input
-     *            the string that caused the exception.
-     * @param reason
-     *            the reason why the exception occurred.
-     * @param index
-     *            the position where the exception occurred.
-     * @throws NullPointerException
-     *             if one of the arguments {@code input} or {@code reason} is
-     *             {@code null}.
-     * @throws IllegalArgumentException
-     *             if the value for {@code index} is lesser than {@code -1}.
-     */
-    public TURISyntaxException(TString input, TString reason, int index) {
         super(reason);
 
         if (input == null || reason == null) {
@@ -65,19 +39,7 @@ public class TURISyntaxException extends TException {
         this.index = index;
     }
 
-    /**
+    public TURISyntaxException(String input, String reason) {
-     * Constructs a new {@code URISyntaxException} instance containing the
-     * string that caused the exception and a description of the problem.
-     *
-     *@param input
-     *            the string that caused the exception.
-     * @param reason
-     *            the reason why the exception occurred.
-     * @throws NullPointerException
-     *             if one of the arguments {@code input} or {@code reason} is
-     *             {@code null}.
-     */
-    public TURISyntaxException(TString input, TString reason) {
         super(reason);
 
         if (input == null || reason == null) {
@@ -88,45 +50,21 @@ public class TURISyntaxException extends TException {
         index = -1;
     }
 
-    /**
-     * Gets the index at which the syntax error was found or {@code -1} if the
-     * index is unknown/unavailable.
-     *
-     * @return the index of the syntax error.
-     */
     public int getIndex() {
         return index;
     }
 
-    /**
+    public String getReason() {
-     * Gets a description of the syntax error.
+        return super.getMessage();
-     *
-     * @return the string describing the syntax error.
-     */
-    public TString getReason() {
-        return TString.wrap(super.getMessage());
     }
 
-    /**
+    public String getInput() {
-     * Gets the initial string that contains an invalid syntax.
-     *
-     * @return the string that caused the exception.
-     */
-    public TString getInput() {
         return input;
     }
 
-    /**
-     * Gets a description of the exception, including the reason, the string
-     * that caused the syntax error and the position of the syntax error if
-     * available.
-     *
-     * @return a sting containing information about the exception.
-     * @see java.lang.Throwable#getMessage()
-     */
     @Override
     @Rename("getMessage")
-    public TString getMessage0() {
+    public String getMessage0() {
-        return TString.wrap("");
+        return "";
     }
 }

classlib/src/main/java/org/teavm/classlib/java/net/TURL.java

@@ -22,7 +22,6 @@ import java.io.Serializable;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Objects;
-import org.teavm.classlib.java.lang.TString;
 import org.teavm.classlib.java.net.impl.TDummyStreamHandler;
 import org.teavm.classlib.java.net.impl.TXHRStreamHandler;
 
@@ -316,7 +315,7 @@ public final class TURL implements Serializable {
     }
 
     public TURI toURI() throws TURISyntaxException {
-        return new TURI((TString) (Object) toExternalForm());
+        return new TURI(toExternalForm());
     }
 
     @Override

classlib/src/main/java/org/teavm/classlib/java/security/TAccessControlException.java

@@ -16,18 +16,17 @@
 package org.teavm.classlib.java.security;
 
 import org.teavm.classlib.java.lang.TSecurityException;
-import org.teavm.classlib.java.lang.TString;
 
 public class TAccessControlException extends TSecurityException {
     private static final long serialVersionUID = 8282514874369266797L;
     private TPermission permission;
 
-    public TAccessControlException(TString message) {
+    public TAccessControlException(String message) {
         super(message);
     }
 
     public TAccessControlException(String s, TPermission permission) {
-        super((TString) (Object) s);
+        super(s);
         this.permission = permission;
     }
 

classlib/src/main/java/org/teavm/classlib/java/text/TDecimalFormat.java

@@ -19,11 +19,9 @@ import java.math.BigDecimal;
 import java.math.BigInteger;
 import java.text.DecimalFormatSymbols;
 import java.util.Arrays;
-
 import org.teavm.classlib.impl.unicode.CLDRHelper;
 import org.teavm.classlib.java.lang.TArithmeticException;
 import org.teavm.classlib.java.lang.TDouble;
-import org.teavm.classlib.java.lang.TString;
 import org.teavm.classlib.java.util.TLocale;
 
 public class TDecimalFormat extends TNumberFormat {
@@ -984,7 +982,7 @@ public class TDecimalFormat extends TNumberFormat {
                 break;
             case UNNECESSARY:
                 if (mantissa % rounding != 0) {
-                    throw new TArithmeticException(TString.wrap("Can't avoid rounding"));
+                    throw new TArithmeticException("Can't avoid rounding");
                 }
                 break;
             case HALF_DOWN:
@@ -1040,7 +1038,7 @@ public class TDecimalFormat extends TNumberFormat {
                 break;
             case UNNECESSARY:
                 if (mantissa.remainder(rounding).equals(BigInteger.ZERO)) {
-                    throw new TArithmeticException(TString.wrap("Can't avoid rounding"));
+                    throw new TArithmeticException("Can't avoid rounding");
                 }
                 break;
             case HALF_DOWN:

classlib/src/main/java/org/teavm/classlib/java/util/TArrays.java

@@ -22,7 +22,6 @@ import java.util.function.IntFunction;
 import java.util.function.IntToDoubleFunction;
 import java.util.function.IntToLongFunction;
 import java.util.function.IntUnaryOperator;
-import org.teavm.classlib.java.lang.TClass;
 import org.teavm.classlib.java.lang.TComparable;
 import org.teavm.classlib.java.lang.TDouble;
 import org.teavm.classlib.java.lang.TFloat;
@@ -30,9 +29,7 @@ import org.teavm.classlib.java.lang.TIllegalArgumentException;
 import org.teavm.classlib.java.lang.TInteger;
 import org.teavm.classlib.java.lang.TMath;
 import org.teavm.classlib.java.lang.TObject;
-import org.teavm.classlib.java.lang.TString;
 import org.teavm.classlib.java.lang.TStringBuilder;
-import org.teavm.classlib.java.lang.reflect.TArray;
 import org.teavm.classlib.java.util.stream.TDoubleStream;
 import org.teavm.classlib.java.util.stream.TIntStream;
 import org.teavm.classlib.java.util.stream.TLongStream;
@@ -126,12 +123,12 @@ public class TArrays extends TObject {
     }
 
     @SuppressWarnings("unchecked")
-    public static <T, U> T[] copyOf(U[] original, int newLength, TClass<? extends T[]> cls) {
+    public static <T, U> T[] copyOf(U[] original, int newLength, Class<? extends T[]> cls) {
-        TClass<?> componentType = cls.getComponentType();
+        Class<?> componentType = cls.getComponentType();
-        T[] result = (T[]) (Object) TArray.newInstance(componentType, newLength);
+        T[] result = (T[]) Array.newInstance(componentType, newLength);
         int sz = TMath.min(newLength, original.length);
         for (int i = 0; i < sz; ++i) {
-            result[i] = (T) componentType.cast(TObject.wrap(original[i]));
+            result[i] = (T) componentType.cast(original[i]);
         }
         return result;
     }
@@ -210,130 +207,130 @@ public class TArrays extends TObject {
     }
 
     @SuppressWarnings("unchecked")
-    public static <T, U> T[] copyOfRange(U[] original, int from, int to, TClass<? extends T[]> newType) {
+    public static <T, U> T[] copyOfRange(U[] original, int from, int to, Class<? extends T[]> newType) {
-        TClass<?> componentType = newType.getComponentType();
+        Class<?> componentType = newType.getComponentType();
-        T[] result = (T[]) (Object) TArray.newInstance(componentType, to - from);
+        T[] result = (T[]) (Object) Array.newInstance(componentType, to - from);
         for (int i = from; i < to; ++i) {
-            result[i - from] = (T) newType.getComponentType().cast(TObject.wrap(original[i]));
+            result[i - from] = (T) newType.getComponentType().cast(original[i]);
         }
         return result;
     }
 
-    public static TString toString(TObject[] a) {
+    public static String toString(TObject[] a) {
         TStringBuilder sb = new TStringBuilder();
-        sb.append(TString.wrap("["));
+        sb.append("[");
         for (int i = 0; i < a.length; ++i) {
             if (i > 0) {
-                sb.append(TString.wrap(", "));
+                sb.append(", ");
             }
             sb.append(a[i]);
         }
-        sb.append(TString.wrap("]"));
+        sb.append("]");
-        return TString.wrap(sb.toString());
+        return sb.toString();
     }
 
-    public static TString toString(boolean[] a) {
+    public static String toString(boolean[] a) {
         TStringBuilder sb = new TStringBuilder();
-        sb.append(TString.wrap("["));
+        sb.append("[");
         for (int i = 0; i < a.length; ++i) {
             if (i > 0) {
-                sb.append(TString.wrap(", "));
+                sb.append(", ");
             }
             sb.append(a[i]);
         }
-        sb.append(TString.wrap("]"));
+        sb.append("]");
-        return TString.wrap(sb.toString());
+        return sb.toString();
     }
 
-    public static TString toString(byte[] a) {
+    public static String toString(byte[] a) {
         TStringBuilder sb = new TStringBuilder();
-        sb.append(TString.wrap("["));
+        sb.append("[");
         for (int i = 0; i < a.length; ++i) {
             if (i > 0) {
-                sb.append(TString.wrap(", "));
+                sb.append(", ");
             }
             sb.append(a[i]);
         }
-        sb.append(TString.wrap("]"));
+        sb.append("]");
-        return TString.wrap(sb.toString());
+        return sb.toString();
     }
 
-    public static TString toString(short[] a) {
+    public static String toString(short[] a) {
         TStringBuilder sb = new TStringBuilder();
-        sb.append(TString.wrap("["));
+        sb.append("[");
         for (int i = 0; i < a.length; ++i) {
             if (i > 0) {
-                sb.append(TString.wrap(", "));
+                sb.append(", ");
             }
             sb.append(a[i]);
         }
-        sb.append(TString.wrap("]"));
+        sb.append("]");
-        return TString.wrap(sb.toString());
+        return sb.toString();
     }
 
-    public static TString toString(char[] a) {
+    public static String toString(char[] a) {
         TStringBuilder sb = new TStringBuilder();
-        sb.append(TString.wrap("["));
+        sb.append("[");
         for (int i = 0; i < a.length; ++i) {
             if (i > 0) {
-                sb.append(TString.wrap(", "));
+                sb.append(", ");
             }
             sb.append(a[i]);
         }
-        sb.append(TString.wrap("]"));
+        sb.append("]");
-        return TString.wrap(sb.toString());
+        return sb.toString();
     }
 
-    public static TString toString(int[] a) {
+    public static String toString(int[] a) {
         TStringBuilder sb = new TStringBuilder();
-        sb.append(TString.wrap("["));
+        sb.append("[");
         for (int i = 0; i < a.length; ++i) {
             if (i > 0) {
-                sb.append(TString.wrap(", "));
+                sb.append(", ");
             }
             sb.append(a[i]);
         }
-        sb.append(TString.wrap("]"));
+        sb.append("]");
-        return TString.wrap(sb.toString());
+        return sb.toString();
     }
 
-    public static TString toString(long[] a) {
+    public static String toString(long[] a) {
         TStringBuilder sb = new TStringBuilder();
-        sb.append(TString.wrap("["));
+        sb.append("[");
         for (int i = 0; i < a.length; ++i) {
             if (i > 0) {
-                sb.append(TString.wrap(", "));
+                sb.append(", ");
             }
             sb.append(a[i]);
         }
-        sb.append(TString.wrap("]"));
+        sb.append("]");
-        return TString.wrap(sb.toString());
+        return sb.toString();
     }
 
-    public static TString toString(float[] a) {
+    public static String toString(float[] a) {
         TStringBuilder sb = new TStringBuilder();
-        sb.append(TString.wrap("["));
+        sb.append("[");
         for (int i = 0; i < a.length; ++i) {
             if (i > 0) {
-                sb.append(TString.wrap(", "));
+                sb.append(", ");
             }
             sb.append(a[i]);
         }
-        sb.append(TString.wrap("]"));
+        sb.append("]");
-        return TString.wrap(sb.toString());
+        return sb.toString();
     }
 
-    public static TString toString(double[] a) {
+    public static String toString(double[] a) {
         TStringBuilder sb = new TStringBuilder();
-        sb.append(TString.wrap("["));
+        sb.append("[");
         for (int i = 0; i < a.length; ++i) {
             if (i > 0) {
-                sb.append(TString.wrap(", "));
+                sb.append(", ");
             }
             sb.append(a[i]);
         }
-        sb.append(TString.wrap("]"));
+        sb.append("]");
-        return TString.wrap(sb.toString());
+        return sb.toString();
     }
 
     public static void fill(long[] a, int fromIndex, int toIndex, long val) {
@@ -1529,22 +1526,22 @@ public class TArrays extends TObject {
         }
     }
 
-    public static TString deepToString(Object[] a) {
+    public static String deepToString(Object[] a) {
-        TStringBuilder sb = new TStringBuilder();
+        StringBuilder sb = new StringBuilder();
         deepToString(a, sb, new TArrayList<>());
-        return TString.wrap(sb.toString());
+        return sb.toString();
     }
 
-    private static void deepToString(Object[] a, TStringBuilder out, TList<Object[]> visited) {
+    private static void deepToString(Object[] a, StringBuilder out, TList<Object[]> visited) {
         out.append('[');
         if (visited.contains(a)) {
-            out.append(TString.wrap("..."));
+            out.append("...");
         } else {
             visited.add(a);
             if (a.length > 0) {
                 deepToString(a[0], out, visited);
                 for (int i = 1; i < a.length; ++i) {
-                    out.append(TString.wrap(", "));
+                    out.append(", ");
                     deepToString(a[i], out, visited);
                 }
             }
@@ -1553,11 +1550,11 @@ public class TArrays extends TObject {
         out.append(']');
     }
 
-    private static void deepToString(Object a, TStringBuilder out, TList<Object[]> visited) {
+    private static void deepToString(Object a, StringBuilder out, TList<Object[]> visited) {
         if (a instanceof Object[]) {
             deepToString((Object[]) a, out, visited);
         } else {
-            out.append(TObject.wrap(a));
+            out.append(a);
         }
     }
 

classlib/src/main/java/org/teavm/classlib/java/util/TCheckedCollection.java

@@ -15,14 +15,11 @@
  */
 package org.teavm.classlib.java.util;
 
-import org.teavm.classlib.java.lang.TClass;
-import org.teavm.classlib.java.lang.TObject;
-
 class TCheckedCollection<E> implements TCollection<E> {
     TCollection<E> innerCollection;
-    TClass<E> type;
+    Class<E> type;
 
-    public TCheckedCollection(TCollection<E> innerCollection, TClass<E> type) {
+    public TCheckedCollection(TCollection<E> innerCollection, Class<E> type) {
         this.innerCollection = innerCollection;
         this.type = type;
     }
@@ -59,7 +56,7 @@ class TCheckedCollection<E> implements TCollection<E> {
 
     @Override
     public boolean add(E e) {
-        return innerCollection.add(type.cast(TObject.wrap(e)));
+        return innerCollection.add(type.cast(e));
     }
 
     @Override
@@ -77,7 +74,7 @@ class TCheckedCollection<E> implements TCollection<E> {
     public boolean addAll(TCollection<? extends E> c) {
         Object[] items = c.toArray();
         for (int i = 0; i < items.length; ++i) {
-            items[i] = type.cast(TObject.wrap(items[i]));
+            items[i] = type.cast(items[i]);
         }
         return innerCollection.addAll(TArrays.asList((E[]) items));
     }

classlib/src/main/java/org/teavm/classlib/java/util/TCheckedList.java

@@ -15,13 +15,10 @@
  */
 package org.teavm.classlib.java.util;
 
-import org.teavm.classlib.java.lang.TClass;
-import org.teavm.classlib.java.lang.TObject;
-
 class TCheckedList<E> extends TCheckedCollection<E> implements TList<E> {
     private TList<E> innerList;
 
-    public TCheckedList(TList<E> innerList, TClass<E> type) {
+    public TCheckedList(TList<E> innerList, Class<E> type) {
         super(innerList, type);
         this.innerList = innerList;
     }
@@ -31,7 +28,7 @@ class TCheckedList<E> extends TCheckedCollection<E> implements TList<E> {
     public boolean addAll(int index, TCollection<? extends E> c) {
         Object[] items = c.toArray();
         for (int i = 0; i < items.length; ++i) {
-            items[i] = type.cast(TObject.wrap(items[i]));
+            items[i] = type.cast(items[i]);
         }
         return innerList.addAll(index, TArrays.asList((E[]) items));
     }
@@ -43,12 +40,12 @@ class TCheckedList<E> extends TCheckedCollection<E> implements TList<E> {
 
     @Override
     public E set(int index, E element) {
-        return innerList.set(index, type.cast(TObject.wrap(element)));
+        return innerList.set(index, type.cast(element));
     }
 
     @Override
     public void add(int index, E element) {
-        innerList.add(index, type.cast(TObject.wrap(element)));
+        innerList.add(index, type.cast(element));
     }
 
     @Override

classlib/src/main/java/org/teavm/classlib/java/util/TCheckedListIterator.java

@@ -15,14 +15,11 @@
  */
 package org.teavm.classlib.java.util;
 
-import org.teavm.classlib.java.lang.TClass;
-import org.teavm.classlib.java.lang.TObject;
-
 class TCheckedListIterator<E> implements TListIterator<E> {
     private TListIterator<E> innerIterator;
-    private TClass<E> type;
+    private Class<E> type;
 
-    public TCheckedListIterator(TListIterator<E> innerIterator, TClass<E> type) {
+    TCheckedListIterator(TListIterator<E> innerIterator, Class<E> type) {
         this.innerIterator = innerIterator;
         this.type = type;
     }
@@ -64,11 +61,11 @@ class TCheckedListIterator<E> implements TListIterator<E> {
 
     @Override
     public void set(E e) {
-        innerIterator.set(type.cast(TObject.wrap(e)));
+        innerIterator.set(type.cast(e));
     }
 
     @Override
     public void add(E e) {
-        innerIterator.add(type.cast(TObject.wrap(e)));
+        innerIterator.add(type.cast(e));
     }
 }

classlib/src/main/java/org/teavm/classlib/java/util/TCheckedMap.java

@@ -15,15 +15,12 @@
  */
 package org.teavm.classlib.java.util;
 
-import org.teavm.classlib.java.lang.TClass;
-import org.teavm.classlib.java.lang.TObject;
-
 class TCheckedMap<K, V> implements TMap<K, V> {
     private TMap<K, V> innerMap;
-    private TClass<K> keyType;
+    private Class<K> keyType;
-    private TClass<V> valueType;
+    private Class<V> valueType;
 
-    public TCheckedMap(TMap<K, V> innerMap, TClass<K> keyType, TClass<V> valueType) {
+    public TCheckedMap(TMap<K, V> innerMap, Class<K> keyType, Class<V> valueType) {
         this.innerMap = innerMap;
         this.keyType = keyType;
         this.valueType = valueType;
@@ -56,7 +53,7 @@ class TCheckedMap<K, V> implements TMap<K, V> {
 
     @Override
     public V put(K key, V value) {
-        return innerMap.put(keyType.cast(TObject.wrap(key)), valueType.cast(TObject.wrap(value)));
+        return innerMap.put(keyType.cast(key), valueType.cast(value));
     }
 
     @Override
@@ -69,8 +66,8 @@ class TCheckedMap<K, V> implements TMap<K, V> {
         m = new THashMap<>(m);
         for (TIterator<? extends Entry<? extends K, ? extends V>> iter = m.entrySet().iterator(); iter.hasNext();) {
             Entry<? extends K, ? extends V> entry = iter.next();
-            keyType.cast(TObject.wrap(entry.getKey()));
+            keyType.cast(entry.getKey());
-            valueType.cast(TObject.wrap(entry.getValue()));
+            valueType.cast(entry.getValue());
         }
         innerMap.putAll(m);
     }

classlib/src/main/java/org/teavm/classlib/java/util/TCheckedSet.java

@@ -15,10 +15,8 @@
  */
 package org.teavm.classlib.java.util;
 
-import org.teavm.classlib.java.lang.TClass;
-
 class TCheckedSet<E> extends TCheckedCollection<E> implements TSet<E> {
-    public TCheckedSet(TCollection<E> innerCollection, TClass<E> type) {
+    public TCheckedSet(TCollection<E> innerCollection, Class<E> type) {
         super(innerCollection, type);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/util/TCollections.java

@@ -572,19 +572,19 @@ public class TCollections extends TObject {
         return list;
     }
 
-    public static <E> TCollection<E> checkedCollection(TCollection<E> c, TClass<E> type) {
+    public static <E> TCollection<E> checkedCollection(TCollection<E> c, Class<E> type) {
         return new TCheckedCollection<>(c, type);
     }
 
-    public static <E> TSet<E> checkedSet(TSet<E> s, TClass<E> type) {
+    public static <E> TSet<E> checkedSet(TSet<E> s, Class<E> type) {
         return new TCheckedSet<>(s, type);
     }
 
-    public static <E> TList<E> checkedList(TList<E> list, TClass<E> type) {
+    public static <E> TList<E> checkedList(TList<E> list, Class<E> type) {
         return new TCheckedList<>(list, type);
     }
 
-    public static <K, V> TMap<K, V> checkedMap(TMap<K, V> m, TClass<K> keyType, TClass<V> valueType) {
+    public static <K, V> TMap<K, V> checkedMap(TMap<K, V> m, Class<K> keyType, Class<V> valueType) {
         return new TCheckedMap<>(m, keyType, valueType);
     }
 

classlib/src/main/java/org/teavm/classlib/java/util/TConcurrentModificationException.java

@@ -16,7 +16,6 @@
 package org.teavm.classlib.java.util;
 
 import org.teavm.classlib.java.lang.TRuntimeException;
-import org.teavm.classlib.java.lang.TString;
 import org.teavm.classlib.java.lang.TThrowable;
 
 public class TConcurrentModificationException extends TRuntimeException {
@@ -26,11 +25,11 @@ public class TConcurrentModificationException extends TRuntimeException {
         super();
     }
 
-    public TConcurrentModificationException(TString message, TThrowable cause) {
+    public TConcurrentModificationException(String message, TThrowable cause) {
         super(message, cause);
     }
 
-    public TConcurrentModificationException(TString message) {
+    public TConcurrentModificationException(String message) {
         super(message);
     }
 

classlib/src/main/java/org/teavm/classlib/java/util/TMissingResourceException.java

@@ -16,7 +16,6 @@
 package org.teavm.classlib.java.util;
 
 import org.teavm.classlib.java.lang.TRuntimeException;
-import org.teavm.classlib.java.lang.TString;
 
 public class TMissingResourceException extends TRuntimeException {
     private static final long serialVersionUID = 6730397307327337970L;
@@ -24,7 +23,7 @@ public class TMissingResourceException extends TRuntimeException {
     private String key;
 
     public TMissingResourceException(String s, String className, String key) {
-        super(TString.wrap(s));
+        super(s);
         this.className = className;
         this.key = key;
     }

classlib/src/main/java/org/teavm/classlib/java/util/TNoSuchElementException.java

@@ -16,7 +16,6 @@
 package org.teavm.classlib.java.util;
 
 import org.teavm.classlib.java.lang.TRuntimeException;
-import org.teavm.classlib.java.lang.TString;
 
 public class TNoSuchElementException extends TRuntimeException {
     private static final long serialVersionUID = -4890604137042866919L;
@@ -25,7 +24,7 @@ public class TNoSuchElementException extends TRuntimeException {
         super();
     }
 
-    public TNoSuchElementException(TString message) {
+    public TNoSuchElementException(String message) {
         super(message);
     }
 }

classlib/src/main/java/org/teavm/classlib/java/util/TProperties.java

@@ -15,14 +15,13 @@
  */
 package org.teavm.classlib.java.util;
 
+import java.io.IOException;
+import java.io.OutputStream;
+import java.io.OutputStreamWriter;
+import java.io.Writer;
 import org.teavm.classlib.java.io.TBufferedInputStream;
-import org.teavm.classlib.java.io.TIOException;
 import org.teavm.classlib.java.io.TInputStream;
-import org.teavm.classlib.java.io.TOutputStream;
-import org.teavm.classlib.java.io.TOutputStreamWriter;
 import org.teavm.classlib.java.io.TPrintStream;
-import org.teavm.classlib.java.io.TWriter;
-import org.teavm.classlib.java.lang.TString;
 
 public class TProperties extends THashtable<Object, Object> {
     /**
@@ -139,17 +138,17 @@ public class TProperties extends THashtable<Object, Object> {
             }
             if (property.length() > 40) {
                 buffer.append(property.substring(0, 37));
-                buffer.append("..."); //$NON-NLS-1$
+                buffer.append("...");
             } else {
                 buffer.append(property);
             }
-            out.println(TString.wrap(buffer.toString()));
+            out.println(buffer.toString());
             buffer.setLength(0);
         }
     }
 
     @SuppressWarnings("fallthrough")
-    public synchronized void load(TInputStream in) throws TIOException {
+    public synchronized void load(TInputStream in) throws IOException {
         if (in == null) {
             throw new NullPointerException();
         }
@@ -339,10 +338,10 @@ public class TProperties extends THashtable<Object, Object> {
     }
 
     @Deprecated
-    public void save(TOutputStream out, String comment) {
+    public void save(OutputStream out, String comment) {
         try {
             store(out, comment);
-        } catch (TIOException e) {
+        } catch (IOException e) {
             // do nothing
         }
     }
@@ -351,8 +350,8 @@ public class TProperties extends THashtable<Object, Object> {
         return put(name, value);
     }
 
-    public synchronized void store(TOutputStream out, String comments) throws TIOException {
+    public synchronized void store(OutputStream out, String comments) throws IOException {
-        TOutputStreamWriter writer = new TOutputStreamWriter(out, "ISO8859_1");
+        OutputStreamWriter writer = new OutputStreamWriter(out, "ISO8859_1");
         if (comments != null) {
             writeComments(writer, comments);
         }
@@ -374,7 +373,7 @@ public class TProperties extends THashtable<Object, Object> {
         writer.flush();
     }
 
-    private void writeComments(TWriter writer, String comments) throws TIOException {
+    private void writeComments(Writer writer, String comments) throws IOException {
         writer.write('#');
         char[] chars = comments.toCharArray();
         for (int index = 0; index < chars.length; index++) {