nw.rar_Internet/IE编程

/* * Copyright (c) 2000, 2010, 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); } 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; } // [C2..DF] [80..BF] private static boolean isMalformed2(int b1, int b2) { return (b1 & 0x1e) == 0x0 || (b2 & 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; } // [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; } 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: int b1 = src.get(); if ((b1 >> 2) == -2) { // 5 bytes 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx if (src.remaining() < 4) return CoderResult.UNDERFLOW; return lookupN(src, 5); } if ((b1 >> 1) == -2) { // 6 bytes 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx if (src.remaining() < 5) return CoderResult.UNDERFLOW; return lookupN(src, 6); } return CoderResult.malformedForLength(1); case 2: // always 1 return CoderResult.malformedForLength(1); case 3: 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 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) { CoderResult cr = (nb == 0 || src.remaining() < (nb - 1)) ?CoderResult.UNDERFLOW:CoderResult.OVERFLOW; src.position(mark); return cr; } 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.m