Fix bugs that were found by FindBugs. Fix

https://github.com/konsoletyper/teavm/issues/46
https://github.com/konsoletyper/teavm/issues/45
https://github.com/konsoletyper/teavm/issues/44
https://github.com/konsoletyper/teavm/issues/42

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

@@ -64,7 +64,7 @@ public class TBufferedInputStream extends TFilterInputStream {
             if (result > 0) {
                 markpos = -1;
                 pos = 0;
-                count = result == -1 ? 0 : result;
+                count = result;
             }
             return result;
         }

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

@@ -38,7 +38,7 @@ public class TFilterOutputStream extends TOutputStream {
         } catch (TIOException e) {
             // do nothing
         }
-        close();
+        out.close();
     }
 
     @Override

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

@@ -200,7 +200,7 @@ public class TStringBuffer extends TAbstractStringBuilder implements TAppendable
 
     @Override
     public TStringBuffer deleteCharAt(int index) {
-        deleteCharAt(index);
+        super.deleteCharAt(index);
         return this;
     }
 

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

@@ -200,7 +200,7 @@ public class TStringBuilder extends TAbstractStringBuilder implements TAppendabl
 
     @Override
     public TStringBuilder deleteCharAt(int index) {
-        deleteCharAt(index);
+        super.deleteCharAt(index);
         return this;
     }
 

teavm-classlib/src/main/java/org/teavm/classlib/java/text/TDateFormatSymbols.java

@@ -109,7 +109,7 @@ public class TDateFormatSymbols implements TSerializable, TCloneable {
                 return false;
             }
             for (int j = 0; j < element.length; j++) {
-                if (element[j] != element[j] && !(element[j].equals(element[j]))) {
+                if (!(element[j].equals(element[j]))) {
                     return false;
                 }
             }

teavm-classlib/src/main/java/org/teavm/classlib/java/util/TBitSet.java

@@ -54,19 +54,21 @@ public class TBitSet extends TObject implements TCloneable, TSerializable {
         int[] ints = new int[(bytes.length + 3) / 4];
         int fullInts = bytes.length / 4;
         for (int i = 0; i < fullInts; ++i) {
-            ints[i] = bytes[i * 4] | (bytes[i * 4 + 1] << 8) | (bytes[i * 4 + 2] << 16) | (bytes[i * 4 + 3] << 24);
+            ints[i] = (bytes[i * 4] & 0xFF) | ((bytes[i * 4 + 1] & 0xFF) << 8) | ((bytes[i * 4 + 2] & 0xFF) << 16) |
+                    ((bytes[i * 4 + 3] & 0xFF) << 24);
         }
         int lastInt = ints.length - 1;
-        int lastByte = bytes[lastInt * 4];
+        int lastByte = lastInt * 4;
         switch (bytes.length % 4) {
             case 3:
-                ints[lastInt] = bytes[lastByte] | (bytes[lastByte + 1] << 8) | (bytes[lastByte + 2] << 16);
+                ints[lastInt] = (bytes[lastByte] & 0xFF) | ((bytes[lastByte + 1] & 0xFF) << 8) |
+                        ((bytes[lastByte + 2] & 0xFF) << 16);
                 break;
             case 2:
-                ints[lastInt] = bytes[lastByte] | (bytes[lastByte + 1] << 8);
+                ints[lastInt] = (bytes[lastByte] & 0xFF) | ((bytes[lastByte + 1] & 0xFF) << 8);
                 break;
             case 1:
-                ints[lastInt] = bytes[lastByte];
+                ints[lastInt] = bytes[lastByte] & 0xFF;
                 break;
         }
         return new TBitSet(ints);
@@ -105,9 +107,9 @@ public class TBitSet extends TObject implements TCloneable, TSerializable {
         int fullLongs = length / 64;
         int i = 0;
         for (; i < fullLongs; ++i) {
-            longs[i] = data[i * 2] | (data[i * 2 + 1] << 32);
+            longs[i] = data[i * 2] | ((long)data[i * 2 + 1] << 32);
         }
-        if (((31 + length) / 32) % 2 == 1) {
+        if ((((31 + length) / 32) & 1) == 1) {
             longs[i] = data[i * 2];
         }
         return longs;

teavm-classlib/src/main/java/org/teavm/classlib/java/util/TRandom.java

@@ -39,7 +39,7 @@ public class TRandom extends TObject implements TSerializable {
     }
 
     public void nextBytes(byte[] bytes) {
-        for (int i = 0; i < bytes.length; ) {
+        for (int i = 0; i < bytes.length; ++i) {
             bytes[i] = (byte)next(8);
         }
     }

teavm-classlib/src/test/java/org/teavm/classlib/java/util/BitSetTest.java

@@ -32,11 +32,11 @@
 package org.teavm.classlib.java.util;
 
 import static org.junit.Assert.*;
+import java.util.Arrays;
 import java.util.BitSet;
 import org.junit.Test;
 
 public class BitSetTest {
-
     BitSet eightbs;
 
     public BitSetTest() {
@@ -58,6 +58,23 @@ public class BitSetTest {
         assertEquals("New BitSet had invalid string representation: " + bs, "{}", bs.toString());
     }
 
+    @Test
+    public void constructFromBytes() {
+        for (int i = 4; i < 8; ++i) {
+            byte[] bytes = new byte[i];
+            Arrays.fill(bytes, (byte)0x80);
+            BitSet bs = BitSet.valueOf(bytes);
+            assertEquals("Wrong length of BitSet", i * 8, bs.length());
+            for (int j = 0; j < bs.length(); ++j) {
+                if (j % 8 == 7) {
+                    assertTrue("Expected that " + j + "th bit is to be set", bs.get(j));
+                } else {
+                    assertFalse("Expected that " + j + "th bit is not to be set", bs.get(j));
+                }
+            }
+        }
+    }
+
     @Test
     public void clonePerformed() {
         BitSet bs;
@@ -76,12 +93,9 @@ public class BitSetTest {
 
         bs = (BitSet) eightbs.clone();
         bs.set(128);
-        assertFalse("Different sized BitSet with higher bit set returned true",
+        assertFalse("Different sized BitSet with higher bit set returned true", eightbs.equals(bs));
-                eightbs.equals(bs));
         bs.clear(128);
-        assertTrue(
+        assertTrue("Different sized BitSet with higher bits not set returned false", eightbs.equals(bs));
-                "Different sized BitSet with higher bits not set returned false",
-                eightbs.equals(bs));
     }
 
     @Test

teavm-core/src/main/java/org/teavm/cache/AstIO.java

@@ -53,10 +53,12 @@ public class AstIO {
         output.writeShort(method.getParameterDebugNames().size());
         for (Set<String> debugNames : method.getParameterDebugNames()) {
             output.writeShort(debugNames != null ? debugNames.size() : 0);
+            if (debugNames != null) {
                 for (String debugName : debugNames) {
                     output.writeUTF(debugName);
                 }
             }
+        }
         output.writeBoolean(method.isOriginalNamePreserved());
         try {
             method.getBody().acceptVisitor(new NodeWriter(output));

teavm-core/src/main/java/org/teavm/debugging/Debugger.java

@@ -224,7 +224,7 @@ public class Debugger {
     }
 
     public Breakpoint createBreakpoint(SourceLocation location) {
-        synchronized (breakpoints) {
+        synchronized (breakpointMap) {
             Breakpoint breakpoint = new Breakpoint(this, location);
             breakpoints.put(breakpoint, dummyObject);
             updateInternalBreakpoints(breakpoint);
@@ -366,7 +366,7 @@ public class Debugger {
             breakpointMap.remove(jsBreakpoint);
         }
         breakpoint.jsBreakpoints = new ArrayList<>();
-        breakpoints.remove(this);
+        breakpoints.remove(breakpoint);
     }
 
     private void fireResumed() {

teavm-core/src/main/java/org/teavm/model/util/InterferenceGraphBuilder.java

@@ -60,7 +60,7 @@ class InterferenceGraphBuilder {
             }
             for (TryCatchBlock tryCatch : block.getTryCatchBlocks()) {
                 if (tryCatch.getExceptionVariable() != null) {
-                    live.remove(tryCatch.getExceptionVariable());
+                    live.remove(nodes.get(tryCatch.getExceptionVariable().getIndex()));
                 }
             }
             for (int j = block.getInstructions().size() - 1; j >= 0; --j) {

teavm-dom/src/main/java/org/teavm/dom/ajax/XMLHttpRequest.java

@@ -63,7 +63,7 @@ public interface XMLHttpRequest extends JSObject {
     Document getResponseXML();
 
     @JSProperty
-    Integer getStatus();
+    int getStatus();
 
     @JSProperty
     String getStatusText();