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/* * Copyright (c) 1997, 2002, 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.io; /** * @author Limin Shi */ public abstract class CharToByteDoubleByte extends CharToByteConverter {     /*     * 1st level index, provided by subclass     */    protected short index1[];     /*     * 2nd level index, provided by subclass     */    protected String  index2[];     protected char highHalfZoneCode;     public short[] getIndex1() {        return index1;    }     public String[] getIndex2() {        return index2;    }     public int flush(byte[] output, int outStart, int outEnd)        throws MalformedInputException, ConversionBufferFullException    {        if (highHalfZoneCode != 0) {            highHalfZoneCode = 0;            badInputLength = 0;            throw new MalformedInputException();        }        byteOff = charOff = 0;        return 0;    }     /**     * Converts characters to sequences of bytes.     * Conversions that result in Exceptions can be restarted by calling     * convert again, with appropriately modified parameters.     * @return the characters written to output.     * @param input char array containing text in Unicode     * @param inStart offset in input array     * @param inEnd offset of last byte to be converted     * @param output byte array to receive conversion result     * @param outStart starting offset     * @param outEnd offset of last byte to be written to     * @throw UnsupportedCharacterException for any character     * that cannot be converted to the external character set.     */    public int convert(char[] input, int inOff, int inEnd,                       byte[] output, int outOff, int outEnd)        throws MalformedInputException, UnknownCharacterException,               ConversionBufferFullException    {        char    inputChar;                 // Input character to be converted        byte[]  outputByte;                // Output byte written to output        int     inputSize = 0;             // Size of input        int     outputSize = 0;            // Size of output        byte[]  tmpbuf = new byte[2];         // Record beginning offsets        charOff = inOff;        byteOff = outOff;         if (highHalfZoneCode != 0) {            inputChar = highHalfZoneCode;            highHalfZoneCode = 0;            if (input[inOff] >= 0xdc00 && input[inOff] <= 0xdfff) {                // This is legal UTF16 sequence.                badInputLength = 1;                throw new UnknownCharacterException();            } else {                // This is illegal UTF16 sequence.                badInputLength = 0;                throw new MalformedInputException();            }        }         // Loop until we hit the end of the input        while(charOff < inEnd) {            inputSize = 1;            outputByte = tmpbuf;            inputChar = input[charOff]; // Get the input character             // Is this a high surrogate?            if(inputChar >= '\uD800' && inputChar <= '\uDBFF') {                // Is this the last character of the input?                if (charOff + 1 >= inEnd) {                    highHalfZoneCode = inputChar;                    break;                }                 // Is there a low surrogate following?                inputChar = input[charOff + 1];                if (inputChar >= '\uDC00' && inputChar <= '\uDFFF') {                    // We have a valid surrogate pair.  Too bad we don't do                    // surrogates.  Is substitution enabled?                    if (subMode) {                        outputByte = subBytes;                        outputSize = subBytes.length;                        inputSize = 2;                    } else {                        badInputLength = 2;                        throw new UnknownCharacterException();                    }                } else {                    // We have a malformed surrogate pair                    badInputLength = 1;                    throw new MalformedInputException();                }            }            // Is this an unaccompanied low surrogate?            else if (inputChar >= '\uDC00' && inputChar <= '\uDFFF') {                badInputLength = 1;                throw new MalformedInputException();            } else {                outputSize = convSingleByte(inputChar, outputByte);                if (outputSize == 0) { // DoubleByte                    int ncode = getNative(inputChar);                    if (ncode != 0 ) {                        outputByte[0] = (byte) ((ncode & 0xff00) >> 8);                        outputByte[1] = (byte) (ncode & 0xff);                        outputSize = 2;                    } else {                        if (subMode) {                            outputByte = subBytes;                            outputSize = subBytes.length;                        } else {                            badInputLength = 1;                            throw new UnknownCharacterException();                        }                    }                }            }             // If we don't have room for the output, throw an exception            if (byteOff + outputSize > outEnd)                throw new ConversionBufferFullException();             // Put the byte in the output buffer            for (int i = 0; i < outputSize; i++) {                output[byteOff++] = outputByte[i];            }            charOff += inputSize;        }        // Return the length written to the output buffer        return byteOff - outOff;    }      /**     * the maximum number of bytes needed to hold a converted char     * @returns the maximum number of bytes needed for a converted char     */    public int getMaxBytesPerChar() {        return 2;    }     /**     *  Resets the converter.     * Call this method to reset the converter to its initial state     */    public void reset() {        byteOff = charOff = 0;        highHalfZoneCode = 0;    }     /**     * Return whether a character is mappable or not     * @return true if a character is mappable     */    public boolean canConvert(char ch) {        byte[] outByte = new byte[2];         if ((ch == (char) 0) || (convSingleByte(ch, outByte) != 0))            return true;        if (this.getNative(ch) != 0)            return true;        return false;    }      /*     * Can be changed by subclass     */    protected int convSingleByte(char inputChar, byte[] outputByte) {        if (inputChar < 0x80) {            outputByte[0] = (byte)(inputChar & 0x7f);            return 1;        }        return 0;    }     /*     * Can be changed by subclass     */    protected int getNative(char ch) {        int offset = index1[((ch & 0xff00) >> 8 )] << 8;        return index2[offset >> 12].charAt((offset & 0xfff) + (ch & 0xff));    } }