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Java example source code file (UTF_8.java)
The UTF_8.java Java example source code/* * Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package sun.nio.cs; import java.nio.Buffer; import java.nio.ByteBuffer; import java.nio.CharBuffer; import java.nio.charset.Charset; import java.nio.charset.CharsetDecoder; import java.nio.charset.CharsetEncoder; import java.nio.charset.CoderResult; import java.nio.charset.CodingErrorAction; /* Legal UTF-8 Byte Sequences * * # Code Points Bits Bit/Byte pattern * 1 7 0xxxxxxx * U+0000..U+007F 00..7F * * 2 11 110xxxxx 10xxxxxx * U+0080..U+07FF C2..DF 80..BF * * 3 16 1110xxxx 10xxxxxx 10xxxxxx * U+0800..U+0FFF E0 A0..BF 80..BF * U+1000..U+FFFF E1..EF 80..BF 80..BF * * 4 21 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx * U+10000..U+3FFFF F0 90..BF 80..BF 80..BF * U+40000..U+FFFFF F1..F3 80..BF 80..BF 80..BF * U+100000..U10FFFF F4 80..8F 80..BF 80..BF * */ class UTF_8 extends Unicode { public UTF_8() { super("UTF-8", StandardCharsets.aliases_UTF_8); } public String historicalName() { return "UTF8"; } public CharsetDecoder newDecoder() { return new Decoder(this); } public CharsetEncoder newEncoder() { return new Encoder(this); } private static final void updatePositions(Buffer src, int sp, Buffer dst, int dp) { src.position(sp - src.arrayOffset()); dst.position(dp - dst.arrayOffset()); } private static class Decoder extends CharsetDecoder implements ArrayDecoder { private Decoder(Charset cs) { super(cs, 1.0f, 1.0f); } private static boolean isNotContinuation(int b) { return (b & 0xc0) != 0x80; } // [E0] [A0..BF] [80..BF] // [E1..EF] [80..BF] [80..BF] private static boolean isMalformed3(int b1, int b2, int b3) { return (b1 == (byte)0xe0 && (b2 & 0xe0) == 0x80) || (b2 & 0xc0) != 0x80 || (b3 & 0xc0) != 0x80; } // only used when there is only one byte left in src buffer private static boolean isMalformed3_2(int b1, int b2) { return (b1 == (byte)0xe0 && (b2 & 0xe0) == 0x80) || (b2 & 0xc0) != 0x80; } // [F0] [90..BF] [80..BF] [80..BF] // [F1..F3] [80..BF] [80..BF] [80..BF] // [F4] [80..8F] [80..BF] [80..BF] // only check 80-be range here, the [0xf0,0x80...] and [0xf4,0x90-...] // will be checked by Character.isSupplementaryCodePoint(uc) private static boolean isMalformed4(int b2, int b3, int b4) { return (b2 & 0xc0) != 0x80 || (b3 & 0xc0) != 0x80 || (b4 & 0xc0) != 0x80; } // only used when there is less than 4 bytes left in src buffer private static boolean isMalformed4_2(int b1, int b2) { return (b1 == 0xf0 && b2 == 0x90) || (b2 & 0xc0) != 0x80; } private static boolean isMalformed4_3(int b3) { return (b3 & 0xc0) != 0x80; } private static CoderResult lookupN(ByteBuffer src, int n) { for (int i = 1; i < n; i++) { if (isNotContinuation(src.get())) return CoderResult.malformedForLength(i); } return CoderResult.malformedForLength(n); } private static CoderResult malformedN(ByteBuffer src, int nb) { switch (nb) { case 1: case 2: // always 1 return CoderResult.malformedForLength(1); case 3: int b1 = src.get(); int b2 = src.get(); // no need to lookup b3 return CoderResult.malformedForLength( ((b1 == (byte)0xe0 && (b2 & 0xe0) == 0x80) || isNotContinuation(b2)) ? 1 : 2); case 4: // we don't care the speed here b1 = src.get() & 0xff; b2 = src.get() & 0xff; if (b1 > 0xf4 || (b1 == 0xf0 && (b2 < 0x90 || b2 > 0xbf)) || (b1 == 0xf4 && (b2 & 0xf0) != 0x80) || isNotContinuation(b2)) return CoderResult.malformedForLength(1); if (isNotContinuation(src.get())) return CoderResult.malformedForLength(2); return CoderResult.malformedForLength(3); default: assert false; return null; } } private static CoderResult malformed(ByteBuffer src, int sp, CharBuffer dst, int dp, int nb) { src.position(sp - src.arrayOffset()); CoderResult cr = malformedN(src, nb); updatePositions(src, sp, dst, dp); return cr; } private static CoderResult malformed(ByteBuffer src, int mark, int nb) { src.position(mark); CoderResult cr = malformedN(src, nb); src.position(mark); return cr; } private static CoderResult malformedForLength(ByteBuffer src, int sp, CharBuffer dst, int dp, int malformedNB) { updatePositions(src, sp, dst, dp); return CoderResult.malformedForLength(malformedNB); } private static CoderResult malformedForLength(ByteBuffer src, int mark, int malformedNB) { src.position(mark); return CoderResult.malformedForLength(malformedNB); } private static CoderResult xflow(Buffer src, int sp, int sl, Buffer dst, int dp, int nb) { updatePositions(src, sp, dst, dp); return (nb == 0 || sl - sp < nb) ? CoderResult.UNDERFLOW : CoderResult.OVERFLOW; } private static CoderResult xflow(Buffer src, int mark, int nb) { src.position(mark); return (nb == 0 || src.remaining() < nb) ? CoderResult.UNDERFLOW : CoderResult.OVERFLOW; } private CoderResult decodeArrayLoop(ByteBuffer src, CharBuffer dst) { // This method is optimized for ASCII input. byte[] sa = src.array(); int sp = src.arrayOffset() + src.position(); int sl = src.arrayOffset() + src.limit(); char[] da = dst.array(); int dp = dst.arrayOffset() + dst.position(); int dl = dst.arrayOffset() + dst.limit(); int dlASCII = dp + Math.min(sl - sp, dl - dp); // ASCII only loop while (dp < dlASCII && sa[sp] >= 0) da[dp++] = (char) sa[sp++]; while (sp < sl) { int b1 = sa[sp]; if (b1 >= 0) { // 1 byte, 7 bits: 0xxxxxxx if (dp >= dl) return xflow(src, sp, sl, dst, dp, 1); da[dp++] = (char) b1; sp++; } else if ((b1 >> 5) == -2 && (b1 & 0x1e) != 0) { // 2 bytes, 11 bits: 110xxxxx 10xxxxxx // [C2..DF] [80..BF] if (sl - sp < 2 || dp >= dl) return xflow(src, sp, sl, dst, dp, 2); int b2 = sa[sp + 1]; // Now we check the first byte of 2-byte sequence as // if ((b1 >> 5) == -2 && (b1 & 0x1e) != 0) // no longer need to check b1 against c1 & c0 for // malformed as we did in previous version // (b1 & 0x1e) == 0x0 || (b2 & 0xc0) != 0x80; // only need to check the second byte b2. if (isNotContinuation(b2)) return malformedForLength(src, sp, dst, dp, 1); da[dp++] = (char) (((b1 << 6) ^ b2) ^ (((byte) 0xC0 << 6) ^ ((byte) 0x80 << 0))); sp += 2; } else if ((b1 >> 4) == -2) { // 3 bytes, 16 bits: 1110xxxx 10xxxxxx 10xxxxxx int srcRemaining = sl - sp; if (srcRemaining < 3 || dp >= dl) { if (srcRemaining > 1 && isMalformed3_2(b1, sa[sp + 1])) return malformedForLength(src, sp, dst, dp, 1); return xflow(src, sp, sl, dst, dp, 3); } int b2 = sa[sp + 1]; int b3 = sa[sp + 2]; if (isMalformed3(b1, b2, b3)) return malformed(src, sp, dst, dp, 3); char c = (char) ((b1 << 12) ^ (b2 << 6) ^ (b3 ^ (((byte) 0xE0 << 12) ^ ((byte) 0x80 << 6) ^ ((byte) 0x80 << 0)))); if (Character.isSurrogate(c)) return malformedForLength(src, sp, dst, dp, 3); da[dp++] = c; sp += 3; } else if ((b1 >> 3) == -2) { // 4 bytes, 21 bits: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx int srcRemaining = sl - sp; if (srcRemaining < 4 || dl - dp < 2) { if (srcRemaining > 1 && isMalformed4_2(b1, sa[sp + 1])) return malformedForLength(src, sp, dst, dp, 1); if (srcRemaining > 2 && isMalformed4_3(sa[sp + 2])) return malformedForLength(src, sp, dst, dp, 2); return xflow(src, sp, sl, dst, dp, 4); } int b2 = sa[sp + 1]; int b3 = sa[sp + 2]; int b4 = sa[sp + 3]; int uc = ((b1 << 18) ^ (b2 << 12) ^ (b3 << 6) ^ (b4 ^ (((byte) 0xF0 << 18) ^ ((byte) 0x80 << 12) ^ ((byte) 0x80 << 6) ^ ((byte) 0x80 << 0)))); if (isMalformed4(b2, b3, b4) || // shortest form check !Character.isSupplementaryCodePoint(uc)) { return malformed(src, sp, dst, dp, 4); } da[dp++] = Character.highSurrogate(uc); da[dp++] = Character.lowSurrogate(uc); sp += 4; } else return malformed(src, sp, dst, dp, 1); } return xflow(src, sp, sl, dst, dp, 0); } private CoderResult decodeBufferLoop(ByteBuffer src, CharBuffer dst) { int mark = src.position(); int limit = src.limit(); while (mark < limit) { int b1 = src.get(); if (b1 >= 0) { // 1 byte, 7 bits: 0xxxxxxx if (dst.remaining() < 1) return xflow(src, mark, 1); // overflow dst.put((char) b1); mark++; } else if ((b1 >> 5) == -2 && (b1 & 0x1e) != 0) { // 2 bytes, 11 bits: 110xxxxx 10xxxxxx if (limit - mark < 2|| dst.remaining() < 1) return xflow(src, mark, 2); int b2 = src.get(); if (isNotContinuation(b2)) return malformedForLength(src, mark, 1); dst.put((char) (((b1 << 6) ^ b2) ^ (((byte) 0xC0 << 6) ^ ((byte) 0x80 << 0)))); mark += 2; } else if ((b1 >> 4) == -2) { // 3 bytes, 16 bits: 1110xxxx 10xxxxxx 10xxxxxx int srcRemaining = limit - mark; if (srcRemaining < 3 || dst.remaining() < 1) { if (srcRemaining > 1 && isMalformed3_2(b1, src.get())) return malformedForLength(src, mark, 1); return xflow(src, mark, 3); } int b2 = src.get(); int b3 = src.get(); if (isMalformed3(b1, b2, b3)) return malformed(src, mark, 3); char c = (char) ((b1 << 12) ^ (b2 << 6) ^ (b3 ^ (((byte) 0xE0 << 12) ^ ((byte) 0x80 << 6) ^ ((byte) 0x80 << 0)))); if (Character.isSurrogate(c)) return malformedForLength(src, mark, 3); dst.put(c); mark += 3; } else if ((b1 >> 3) == -2) { // 4 bytes, 21 bits: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx int srcRemaining = limit - mark; if (srcRemaining < 4 || dst.remaining() < 2) { if (srcRemaining > 1 && isMalformed4_2(b1, src.get())) return malformedForLength(src, mark, 1); if (srcRemaining > 2 && isMalformed4_3(src.get())) return malformedForLength(src, mark, 2); return xflow(src, mark, 4); } int b2 = src.get(); int b3 = src.get(); int b4 = src.get(); int uc = ((b1 << 18) ^ (b2 << 12) ^ (b3 << 6) ^ (b4 ^ (((byte) 0xF0 << 18) ^ ((byte) 0x80 << 12) ^ ((byte) 0x80 << 6) ^ ((byte) 0x80 << 0)))); if (isMalformed4(b2, b3, b4) || // shortest form check !Character.isSupplementaryCodePoint(uc)) { return malformed(src, mark, 4); } dst.put(Character.highSurrogate(uc)); dst.put(Character.lowSurrogate(uc)); mark += 4; } else { return malformed(src, mark, 1); } } return xflow(src, mark, 0); } protected CoderResult decodeLoop(ByteBuffer src, CharBuffer dst) { if (src.hasArray() && dst.hasArray()) return decodeArrayLoop(src, dst); else return decodeBufferLoop(src, dst); } private static ByteBuffer getByteBuffer(ByteBuffer bb, byte[] ba, int sp) { if (bb == null) bb = ByteBuffer.wrap(ba); bb.position(sp); return bb; } // returns -1 if there is/are malformed byte(s) and the // "action" for malformed input is not REPLACE. public int decode(byte[] sa, int sp, int len, char[] da) { final int sl = sp + len; int dp = 0; int dlASCII = Math.min(len, da.length); ByteBuffer bb = null; // only necessary if malformed // ASCII only optimized loop while (dp < dlASCII && sa[sp] >= 0) da[dp++] = (char) sa[sp++]; while (sp < sl) { int b1 = sa[sp++]; if (b1 >= 0) { // 1 byte, 7 bits: 0xxxxxxx da[dp++] = (char) b1; } else if ((b1 >> 5) == -2 && (b1 & 0x1e) != 0) { // 2 bytes, 11 bits: 110xxxxx 10xxxxxx if (sp < sl) { int b2 = sa[sp++]; if (isNotContinuation(b2)) { if (malformedInputAction() != CodingErrorAction.REPLACE) return -1; da[dp++] = replacement().charAt(0); sp--; // malformedN(bb, 2) always returns 1 } else { da[dp++] = (char) (((b1 << 6) ^ b2)^ (((byte) 0xC0 << 6) ^ ((byte) 0x80 << 0))); } continue; } if (malformedInputAction() != CodingErrorAction.REPLACE) return -1; da[dp++] = replacement().charAt(0); return dp; } else if ((b1 >> 4) == -2) { // 3 bytes, 16 bits: 1110xxxx 10xxxxxx 10xxxxxx if (sp + 1 < sl) { int b2 = sa[sp++]; int b3 = sa[sp++]; if (isMalformed3(b1, b2, b3)) { if (malformedInputAction() != CodingErrorAction.REPLACE) return -1; da[dp++] = replacement().charAt(0); sp -= 3; bb = getByteBuffer(bb, sa, sp); sp += malformedN(bb, 3).length(); } else { char c = (char)((b1 << 12) ^ (b2 << 6) ^ (b3 ^ (((byte) 0xE0 << 12) ^ ((byte) 0x80 << 6) ^ ((byte) 0x80 << 0)))); if (Character.isSurrogate(c)) { if (malformedInputAction() != CodingErrorAction.REPLACE) return -1; da[dp++] = replacement().charAt(0); } else { da[dp++] = c; } } continue; } if (malformedInputAction() != CodingErrorAction.REPLACE) return -1; if (sp < sl && isMalformed3_2(b1, sa[sp])) { da[dp++] = replacement().charAt(0); continue; } da[dp++] = replacement().charAt(0); return dp; } else if ((b1 >> 3) == -2) { // 4 bytes, 21 bits: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx if (sp + 2 < sl) { int b2 = sa[sp++]; int b3 = sa[sp++]; int b4 = sa[sp++]; int uc = ((b1 << 18) ^ (b2 << 12) ^ (b3 << 6) ^ (b4 ^ (((byte) 0xF0 << 18) ^ ((byte) 0x80 << 12) ^ ((byte) 0x80 << 6) ^ ((byte) 0x80 << 0)))); if (isMalformed4(b2, b3, b4) || // shortest form check !Character.isSupplementaryCodePoint(uc)) { if (malformedInputAction() != CodingErrorAction.REPLACE) return -1; da[dp++] = replacement().charAt(0); sp -= 4; bb = getByteBuffer(bb, sa, sp); sp += malformedN(bb, 4).length(); } else { da[dp++] = Character.highSurrogate(uc); da[dp++] = Character.lowSurrogate(uc); } continue; } if (malformedInputAction() != CodingErrorAction.REPLACE) return -1; if (sp < sl && isMalformed4_2(b1, sa[sp])) { da[dp++] = replacement().charAt(0); continue; } sp++; if (sp < sl && isMalformed4_3(sa[sp])) { da[dp++] = replacement().charAt(0); continue; } da[dp++] = replacement().charAt(0); return dp; } else { if (malformedInputAction() != CodingErrorAction.REPLACE) return -1; da[dp++] = replacement().charAt(0); } } return dp; } } private static final class Encoder extends CharsetEncoder implements ArrayEncoder { private Encoder(Charset cs) { super(cs, 1.1f, 3.0f); } public boolean canEncode(char c) { return !Character.isSurrogate(c); } public boolean isLegalReplacement(byte[] repl) { return ((repl.length == 1 && repl[0] >= 0) || super.isLegalReplacement(repl)); } private static CoderResult overflow(CharBuffer src, int sp, ByteBuffer dst, int dp) { updatePositions(src, sp, dst, dp); return CoderResult.OVERFLOW; } private static CoderResult overflow(CharBuffer src, int mark) { src.position(mark); return CoderResult.OVERFLOW; } private Surrogate.Parser sgp; private CoderResult encodeArrayLoop(CharBuffer src, ByteBuffer dst) { char[] sa = src.array(); int sp = src.arrayOffset() + src.position(); int sl = src.arrayOffset() + src.limit(); byte[] da = dst.array(); int dp = dst.arrayOffset() + dst.position(); int dl = dst.arrayOffset() + dst.limit(); int dlASCII = dp + Math.min(sl - sp, dl - dp); // ASCII only loop while (dp < dlASCII && sa[sp] < '\u0080') da[dp++] = (byte) sa[sp++]; while (sp < sl) { char c = sa[sp]; if (c < 0x80) { // Have at most seven bits if (dp >= dl) return overflow(src, sp, dst, dp); da[dp++] = (byte)c; } else if (c < 0x800) { // 2 bytes, 11 bits if (dl - dp < 2) return overflow(src, sp, dst, dp); da[dp++] = (byte)(0xc0 | (c >> 6)); da[dp++] = (byte)(0x80 | (c & 0x3f)); } else if (Character.isSurrogate(c)) { // Have a surrogate pair if (sgp == null) sgp = new Surrogate.Parser(); int uc = sgp.parse(c, sa, sp, sl); if (uc < 0) { updatePositions(src, sp, dst, dp); return sgp.error(); } if (dl - dp < 4) return overflow(src, sp, dst, dp); da[dp++] = (byte)(0xf0 | ((uc >> 18))); da[dp++] = (byte)(0x80 | ((uc >> 12) & 0x3f)); da[dp++] = (byte)(0x80 | ((uc >> 6) & 0x3f)); da[dp++] = (byte)(0x80 | (uc & 0x3f)); sp++; // 2 chars } else { // 3 bytes, 16 bits if (dl - dp < 3) return overflow(src, sp, dst, dp); da[dp++] = (byte)(0xe0 | ((c >> 12))); da[dp++] = (byte)(0x80 | ((c >> 6) & 0x3f)); da[dp++] = (byte)(0x80 | (c & 0x3f)); } sp++; } updatePositions(src, sp, dst, dp); return CoderResult.UNDERFLOW; } private CoderResult encodeBufferLoop(CharBuffer src, ByteBuffer dst) { int mark = src.position(); while (src.hasRemaining()) { char c = src.get(); if (c < 0x80) { // Have at most seven bits if (!dst.hasRemaining()) return overflow(src, mark); dst.put((byte)c); } else if (c < 0x800) { // 2 bytes, 11 bits if (dst.remaining() < 2) return overflow(src, mark); dst.put((byte)(0xc0 | (c >> 6))); dst.put((byte)(0x80 | (c & 0x3f))); } else if (Character.isSurrogate(c)) { // Have a surrogate pair if (sgp == null) sgp = new Surrogate.Parser(); int uc = sgp.parse(c, src); if (uc < 0) { src.position(mark); return sgp.error(); } if (dst.remaining() < 4) return overflow(src, mark); dst.put((byte)(0xf0 | ((uc >> 18)))); dst.put((byte)(0x80 | ((uc >> 12) & 0x3f))); dst.put((byte)(0x80 | ((uc >> 6) & 0x3f))); dst.put((byte)(0x80 | (uc & 0x3f))); mark++; // 2 chars } else { // 3 bytes, 16 bits if (dst.remaining() < 3) return overflow(src, mark); dst.put((byte)(0xe0 | ((c >> 12)))); dst.put((byte)(0x80 | ((c >> 6) & 0x3f))); dst.put((byte)(0x80 | (c & 0x3f))); } mark++; } src.position(mark); return CoderResult.UNDERFLOW; } protected final CoderResult encodeLoop(CharBuffer src, ByteBuffer dst) { if (src.hasArray() && dst.hasArray()) return encodeArrayLoop(src, dst); else return encodeBufferLoop(src, dst); } private byte repl = (byte)'?'; protected void implReplaceWith(byte[] newReplacement) { repl = newReplacement[0]; } // returns -1 if there is malformed char(s) and the // "action" for malformed input is not REPLACE. public int encode(char[] sa, int sp, int len, byte[] da) { int sl = sp + len; int dp = 0; int dlASCII = dp + Math.min(len, da.length); // ASCII only optimized loop while (dp < dlASCII && sa[sp] < '\u0080') da[dp++] = (byte) sa[sp++]; while (sp < sl) { char c = sa[sp++]; if (c < 0x80) { // Have at most seven bits da[dp++] = (byte)c; } else if (c < 0x800) { // 2 bytes, 11 bits da[dp++] = (byte)(0xc0 | (c >> 6)); da[dp++] = (byte)(0x80 | (c & 0x3f)); } else if (Character.isSurrogate(c)) { if (sgp == null) sgp = new Surrogate.Parser(); int uc = sgp.parse(c, sa, sp - 1, sl); if (uc < 0) { if (malformedInputAction() != CodingErrorAction.REPLACE) return -1; da[dp++] = repl; } else { da[dp++] = (byte)(0xf0 | ((uc >> 18))); da[dp++] = (byte)(0x80 | ((uc >> 12) & 0x3f)); da[dp++] = (byte)(0x80 | ((uc >> 6) & 0x3f)); da[dp++] = (byte)(0x80 | (uc & 0x3f)); sp++; // 2 chars } } else { // 3 bytes, 16 bits da[dp++] = (byte)(0xe0 | ((c >> 12))); da[dp++] = (byte)(0x80 | ((c >> 6) & 0x3f)); da[dp++] = (byte)(0x80 | (c & 0x3f)); } } return dp; } } } Other Java examples (source code examples)Here is a short list of links related to this Java UTF_8.java source code file: |
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