Base64 implementation (#650)

classlib: add Base64 support

classlib/src/main/java/org/teavm/classlib/impl/Base64Impl.java

@@ -18,33 +18,47 @@ package org.teavm.classlib.impl;
 import java.util.Arrays;
 
 public final class Base64Impl {
-    private static byte[] alphabet = new byte[64];
-    private static int[] reverse = new int[256];
+    public static byte[] alphabet = new byte[64];
+    public static byte[] urlAlphabet = new byte[64];
+    public static int[] reverse = new int[256];
+    public static int[] urlReverse = new int[256];
 
     static {
         int i = 0;
         for (char c = 'A'; c <= 'Z'; ++c) {
-            alphabet[i++] = (byte) c;
+            alphabet[i] = (byte) c;
+            urlAlphabet[i] = (byte) c;
+            i++;
         }
         for (char c = 'a'; c <= 'z'; ++c) {
-            alphabet[i++] = (byte) c;
+            alphabet[i] = (byte) c;
+            urlAlphabet[i] = (byte) c;
+            i++;
         }
         for (char c = '0'; c <= '9'; ++c) {
-            alphabet[i++] = (byte) c;
+            alphabet[i] = (byte) c;
+            urlAlphabet[i] = (byte) c;
+            i++;
         }
-        alphabet[i++] = '+';
-        alphabet[i++] = '/';
+        alphabet[i] = '+';
+        urlAlphabet[i] = '-';
+        i++;
+        alphabet[i] = '/';
+        urlAlphabet[i] = '_';
+        i++;
 
         Arrays.fill(reverse, -1);
+        Arrays.fill(urlReverse, -1);
         for (i = 0; i < alphabet.length; ++i) {
             reverse[alphabet[i]] = i;
+            urlReverse[urlAlphabet[i]] = i;
         }
     }
 
     private Base64Impl() {
     }
 
-    public static byte[] decode(byte[] text) {
+    public static byte[] decode(byte[] text, int[] mapping) {
         int outputSize = (text.length / 4) * 3;
         int rem = text.length % 4;
         if (rem == 2 || rem == 3) {
@@ -55,11 +69,15 @@ public final class Base64Impl {
             --outputSize;
         }
         byte[] output = new byte[outputSize];
-        decode(text, output);
+        decode(text, output, mapping);
         return output;
     }
 
-    public static void decode(byte[] text, byte[] output) {
+    public static byte[] decode(byte[] text) {
+        return decode(text, reverse);
+    }
+
+    public static void decode(byte[] text, byte[] output, int[] mapping) {
         int inputSize = text.length;
         int i;
         for (i = text.length - 1; i >= 0 && text[i] == '='; --i) {
@@ -70,10 +88,10 @@ public final class Base64Impl {
         i = 0;
         int j = 0;
         while (i < triples) {
-            int a = decode(text[i++]);
-            int b = decode(text[i++]);
-            int c = decode(text[i++]);
-            int d = decode(text[i++]);
+            int a = decode(mapping, text[i++]);
+            int b = decode(mapping, text[i++]);
+            int c = decode(mapping, text[i++]);
+            int d = decode(mapping, text[i++]);
             int out = (a << 18) | (b << 12) | (c << 6) | d;
             output[j++] = (byte) (out >>> 16);
             output[j++] = (byte) (out >>> 8);
@@ -82,23 +100,23 @@ public final class Base64Impl {
 
         int rem = inputSize - i;
         if (rem == 2) {
-            int a = decode(text[i]);
-            int b = decode(text[i + 1]);
+            int a = decode(mapping, text[i]);
+            int b = decode(mapping, text[i + 1]);
             output[j] = (byte) ((a << 2) | (b >>> 4));
         } else if (rem == 3) {
-            int a = decode(text[i]);
-            int b = decode(text[i + 1]);
-            int c = decode(text[i + 2]);
+            int a = decode(mapping, text[i]);
+            int b = decode(mapping, text[i + 1]);
+            int c = decode(mapping, text[i + 2]);
             output[j] = (byte) ((a << 2) | (b >>> 4));
             output[j + 1] = (byte) ((b << 4) | (c >>> 2));
         }
     }
 
-    private static int decode(byte c) {
-        return reverse[c];
+    private static int decode(int[] mapping, byte c) {
+        return mapping[c];
     }
 
-    public static byte[] encode(byte[] data, boolean pad) {
+    public static byte[] encode(byte[] data, byte[] mapping, boolean pad) {
         int outputSize = ((data.length + 2) / 3) * 4;
         if (!pad) {
             int rem = data.length % 3;
@@ -107,38 +125,42 @@ public final class Base64Impl {
             }
         }
         byte[] output = new byte[outputSize];
-        encode(data, output, pad);
+        encode(data, output, mapping, pad);
         return output;
     }
 
-    public static int encode(byte[] data, byte[] output, boolean pad) {
+    public static byte[] encode(byte[] data, boolean pad) {
+        return encode(data, alphabet, pad);
+    }
+
+    public static int encode(byte[] data, byte[] output, byte[] mapping, boolean pad) {
         int triples = (data.length / 3) * 3;
 
         int i = 0;
         int j;
         for (j = 0; j < triples;) {
-            output[i++] = encode((byte) (data[j] >>> 2));
-            output[i++] = encode((byte) ((data[j] << 4) | ((data[j + 1] & 0xFF) >>> 4)));
+            output[i++] = encode(mapping, (byte) (data[j] >>> 2));
+            output[i++] = encode(mapping, (byte) ((data[j] << 4) | ((data[j + 1] & 0xFF) >>> 4)));
             ++j;
-            output[i++] = encode((byte) ((data[j] << 2) | ((data[j + 1] & 0xFF) >>> 6)));
+            output[i++] = encode(mapping, (byte) ((data[j] << 2) | ((data[j + 1] & 0xFF) >>> 6)));
             ++j;
-            output[i++] = encode(data[j]);
+            output[i++] = encode(mapping, data[j]);
             ++j;
         }
 
         int rem = data.length - j;
         if (rem == 1) {
-            output[i++] = encode((byte) (data[j] >>> 2));
-            output[i++] = encode((byte) (data[j] << 4));
+            output[i++] = encode(mapping, (byte) (data[j] >>> 2));
+            output[i++] = encode(mapping, (byte) (data[j] << 4));
             if (pad) {
                 output[i++] = '=';
                 output[i++] = '=';
             }
         } else if (rem == 2) {
-            output[i++] = encode((byte) (data[j] >>> 2));
-            output[i++] = encode((byte) ((data[j] << 4) | (data[j + 1] >>> 4)));
+            output[i++] = encode(mapping, (byte) (data[j] >>> 2));
+            output[i++] = encode(mapping, (byte) ((data[j] << 4) | ((data[j + 1] & 0xFF) >>> 4)));
             ++j;
-            output[i++] = encode((byte) (data[j] << 2));
+            output[i++] = encode(mapping, (byte) (data[j] << 2));
             if (pad) {
                 output[i++] = '=';
             }
@@ -147,7 +169,7 @@ public final class Base64Impl {
         return i;
     }
 
-    private static byte encode(byte b) {
-        return alphabet[b & 63];
+    private static byte encode(byte[] mapping, byte b) {
+        return mapping[b & 63];
     }
 }

classlib/src/main/java/org/teavm/classlib/java/util/TBase64.java

@@ -0,0 +1,62 @@
+/*
+ *  Copyright 2023 ihromant.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+package org.teavm.classlib.java.util;
+
+import org.teavm.classlib.impl.Base64Impl;
+
+public class TBase64 {
+    public static Encoder getEncoder() {
+        return new Encoder(Base64Impl.alphabet, true);
+    }
+
+    public static Encoder getUrlEncoder() {
+        return new Encoder(Base64Impl.urlAlphabet, false);
+    }
+
+    public static class Encoder {
+        private final byte[] mapping;
+        private final boolean padding;
+
+        private Encoder(byte[] mapping, boolean padding) {
+            this.mapping = mapping;
+            this.padding = padding;
+        }
+
+        public byte[] encode(byte[] src) {
+            return Base64Impl.encode(src, mapping, padding);
+        }
+    }
+
+    public Decoder getDecoder() {
+        return new Decoder(Base64Impl.reverse);
+    }
+
+    public Decoder getUrlDecoder() {
+        return new Decoder(Base64Impl.urlReverse);
+    }
+
+    public static class Decoder {
+        private final int[] mapping;
+
+        private Decoder(int[] mapping) {
+            this.mapping = mapping;
+        }
+
+        public byte[] decode(byte[] src) {
+            return Base64Impl.decode(src, mapping);
+        }
+    }
+}

classlib/src/test/java/org/teavm/classlib/impl/Base64Test.java

@@ -33,6 +33,7 @@ public class Base64Test {
         assertEquals("qwerty", decode("cXdlcnR5"));
         assertEquals("qwertyu", decode("cXdlcnR5dQ=="));
         assertEquals("qwertyu", decode("cXdlcnR5dQ"));
+        assertEquals("юзернейм:пароль", decode("0Y7Qt9C10YDQvdC10LnQvDrQv9Cw0YDQvtC70Yw="));
     }
 
     @Test
@@ -44,6 +45,7 @@ public class Base64Test {
         assertEquals("cXdlcnQ=", encode("qwert"));
         assertEquals("cXdlcnR5", encode("qwerty"));
         assertEquals("cXdlcnR5dQ==", encode("qwertyu"));
+        assertEquals("0Y7Qt9C10YDQvdC10LnQvDrQv9Cw0YDQvtC70Yw=", encode("юзернейм:пароль"));
     }
 
     @Test

tests/src/test/java/org/teavm/classlib/java/util/Base64Test.java

@@ -0,0 +1,99 @@
+/*
+ *  Copyright 2023 ihromant.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+package org.teavm.classlib.impl;
+
+import static org.junit.Assert.*;
+import java.io.UnsupportedEncodingException;
+import org.junit.Test;
+
+@RunWith(TeaVMTestRunner.class)
+@WholeClassCompilation
+public class Base64Test {
+    @Test
+    public void decoderWorks() {
+        Decoder decoder = Base64.getDecoder();
+        assertEquals("q", decoder.decode("cQ=="));
+        assertEquals("qw", decoder.decode("cXc="));
+        assertEquals("qwe", decoder.decode("cXdl"));
+        assertEquals("qwer", decoder.decode("cXdlcg=="));
+        assertEquals("qwert", decoder.decode("cXdlcnQ="));
+        assertEquals("qwerty", decoder.decode("cXdlcnR5"));
+        assertEquals("qwertyu", decoder.decode("cXdlcnR5dQ=="));
+        assertEquals("юзернейм:пароль", decoder.decode("0Y7Qt9C10YDQvdC10LnQvDrQv9Cw0YDQvtC70Yw="));
+    }
+
+    @Test
+    public void encoderWorks() {
+        Encoder encoder = Base64.getEncoder();
+        assertEquals("cQ==", encoder.encode("q"));
+        assertEquals("cXc=", encoder.encode("qw"));
+        assertEquals("cXdl", encoder.encode("qwe"));
+        assertEquals("cXdlcg==", encoder.encode("qwer"));
+        assertEquals("cXdlcnQ=", encoder.encode("qwert"));
+        assertEquals("cXdlcnR5", encoder.encode("qwerty"));
+        assertEquals("cXdlcnR5dQ==", encoder.encode("qwertyu"));
+        assertEquals("0Y7Qt9C10YDQvdC10LnQvDrQv9Cw0YDQvtC70Yw=", encoder.encode("юзернейм:пароль"));
+    }
+
+    @Test
+    public void urlDecoderWorks() {
+        Decoder decoder = Base64.getUrlDecoder();
+        assertEquals("q", decoder.decode("cQ"));
+        assertEquals("qw", decoder.decode("cXc"));
+        assertEquals("qwe", decoder.decode("cXdl"));
+        assertEquals("qwer", decoder.decode("cXdlcg"));
+        assertEquals("qwerty", decoder.decode("cXdlcnR5"));
+        assertEquals("qwertyu", decoder.decode("cXdlcnR5dQ"));
+        assertEquals("юзернейм:пароль", decoder.decode("0Y7Qt9C10YDQvdC10LnQvDrQv9Cw0YDQvtC70Yw"));
+    }
+
+    @Test
+    public void urlEncoderWorks() {
+        Encoder encoder = Base64.getUrlEncoder();
+        assertEquals("cQ", encoder.encodeNoPad("q"));
+        assertEquals("cXc", encoder.encodeNoPad("qw"));
+        assertEquals("cXdl", encoder.encodeNoPad("qwe"));
+        assertEquals("cXdlcg", encoder.encodeNoPad("qwer"));
+        assertEquals("cXdlcnQ", encoder.encodeNoPad("qwert"));
+        assertEquals("cXdlcnR5", encoder.encodeNoPad("qwerty"));
+        assertEquals("cXdlcnR5dQ", encoder.encodeNoPad("qwertyu"));
+        assertEquals("0Y7Qt9C10YDQvdC10LnQvDrQv9Cw0YDQvtC70Yw", encoder.encode("юзернейм:пароль"));
+    }
+
+    private String decode(String text) {
+        try {
+            return new String(Base64Impl.decode(text.getBytes("UTF-8")), "UTF-8");
+        } catch (UnsupportedEncodingException e) {
+            return "";
+        }
+    }
+
+    private String encode(String text) {
+        try {
+            return new String(Base64Impl.encode(text.getBytes("UTF-8"), true), "UTF-8");
+        } catch (UnsupportedEncodingException e) {
+            return "";
+        }
+    }
+
+    private String encodeNoPad(String text) {
+        try {
+            return new String(Base64Impl.encode(text.getBytes("UTF-8"), false), "UTF-8");
+        } catch (UnsupportedEncodingException e) {
+            return "";
+        }
+    }
+}