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/* * Copyright (c) 1996, 2008, 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; import static sun.nio.cs.CharsetMapping.*; /*** A table driven conversion from char to byte for single byte* character sets.  Tables will reside in the class CharToByteYYYYY,* where YYYYY is a unique character set identifier     < TBD: Tables are of the form... > ** @author Lloyd Honomichl* @author Asmus Freytag* @version 8/28/96*/ public abstract class CharToByteSingleByte extends CharToByteConverter {     /*     * 1st level index, provided by subclass     */    protected char[] index1;     /*     * 2nd level index, provided by subclass     */    protected char[] index2;     /*     * Mask to isolate bits for 1st level index, from subclass     */    protected int   mask1;     /*     * Mask to isolate bits for 2nd level index, from subclass     */    protected int   mask2;     /*     * Shift to isolate bits for 1st level index, from subclass     */    protected int   shift;     private char highHalfZoneCode;     public char[] getIndex1() {        return index1;    }     public char[] getIndex2() {        return index2;    }    public int flush(byte[] output, int outStart, int outEnd)        throws MalformedInputException    {        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 MalformedInputException for any sequence of chars that is     * illegal in Unicode (principally unpaired surrogates     * and \uFFFF or \uFFFE), including any partial surrogate pair     * which occurs at the end of an input buffer.     * @throw UnsupportedCharacterException for any character that     * 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;          // Size of input        int     outputSize;         // Size of output         byte[]  tmpArray = new byte[1];         // 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) {             outputByte = tmpArray;             // Get the input character            inputChar = input[charOff];             // Default output size            outputSize = 1;             // Assume this is a simple character            inputSize = 1;             // Is this a high surrogate?            if(inputChar >= '\uD800' && inputChar <= '\uDBFF') {                // Is this the last character in 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 map                    //  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();            }             // Not part of a surrogate, so look it up            else {                // Get output using two level lookup                outputByte[0] = getNative(inputChar);                 // Might this character be unmappable?                if (outputByte[0] == 0) {                    // If outputByte is zero because the input was zero                    //  then this character is actually mappable                    if (input[charOff] != '\u0000') {                        // We have an unmappable character                        // Is substitution enabled?                        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 1;    }     int encodeChar(char ch) {        char index = index1[ch >> 8];        if (index == UNMAPPABLE_ENCODING)            return UNMAPPABLE_ENCODING;        return index2[index + (ch & 0xff)];    }     public byte getNative(char inputChar) {        int b = encodeChar(inputChar);        if (b == UNMAPPABLE_ENCODING)            return 0;        return (byte)b;    }     /**     *  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) {        return encodeChar(ch) != UNMAPPABLE_ENCODING;    }}