1 /*

     2  * Copyright (c) 1997, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Oracle designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Oracle in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    22  * or visit www.oracle.com if you need additional information or have any

    23  * questions.

    24  */

    25 package sun.io;

    26 

    27 public abstract class CharToByteEUC extends CharToByteConverter

    28 {

    29 

    30     private char highHalfZoneCode;

    31     private byte[] outputByte;

    32 

    33     protected short  index1[];

    34     protected String index2;

    35     protected String index2a;

    36     protected String index2b;

    37     protected String index2c;

    38     protected int    mask1;

    39     protected int    mask2;

    40     protected int    shift;

    41 

    42     private byte[] workByte = new byte[4];

    43 

    44     /**

    45       * flush out any residual data and reset the buffer state

    46       */

    47     public int flush(byte [] output, int outStart, int outEnd)

    48         throws MalformedInputException, ConversionBufferFullException

    49     {

    50 

    51        if (highHalfZoneCode != 0) {

    52           reset();

    53           badInputLength = 0;

    54           throw new MalformedInputException();

    55        }

    56 

    57        reset();

    58        return 0;

    59     }

    60 

    61     /**

    62      * Character conversion

    63      */

    64     public int convert(char[] input, int inOff, int inEnd,

    65                        byte[] output, int outOff, int outEnd)

    66         throws UnknownCharacterException, MalformedInputException,

    67                ConversionBufferFullException

    68     {

    69         char    inputChar;

    70         int     inputSize;

    71 

    72         byteOff = outOff;

    73         charOff = inOff;

    74 

    75         while(charOff < inEnd) {

    76 

    77            outputByte = workByte;

    78 

    79            int     index;

    80            int     theBytes;

    81            int     spaceNeeded;

    82            boolean allZeroes = true;

    83            int     i;

    84 

    85 

    86            if (highHalfZoneCode == 0) {

    87               inputChar = input[charOff];

    88               inputSize = 1;

    89            } else {

    90               inputChar = highHalfZoneCode;

    91               inputSize = 0;

    92               highHalfZoneCode = 0;

    93            }

    94 

    95 

    96            // Is this a high surrogate?

    97            if(inputChar >= '\ud800' && inputChar <= '\udbff') {

    98               // Is this the last character of the input?

    99               if (charOff + inputSize >= inEnd) {

   100                  highHalfZoneCode = inputChar;

   101                  charOff += inputSize;

   102                  break;

   103               }

   104 

   105               // Is there a low surrogate following?

   106               inputChar = input[charOff + inputSize];

   107               if (inputChar >= '\udc00' && inputChar <= '\udfff') {

   108 

   109                  // We have a valid surrogate pair.  Too bad we don't do

   110                  // surrogates.  Is substitution enabled?

   111                  if (subMode) {

   112                     outputByte = subBytes;

   113                     inputSize++;

   114                  } else {

   115                     badInputLength = 2;

   116                     throw new UnknownCharacterException();

   117                  }

   118               } else {

   119 

   120                  // We have a malformed surrogate pair

   121                  badInputLength = 1;

   122                  throw new MalformedInputException();

   123               }

   124            }

   125 

   126            // Is this an unaccompanied low surrogate?

   127            else

   128               if (inputChar >= '\uDC00' && inputChar <= '\uDFFF') {

   129                  badInputLength = 1;

   130                  throw new MalformedInputException();

   131               } else {

   132 

   133                  String theChars;

   134                  char   aChar;

   135 

   136                  // We have a valid character, get the bytes for it

   137                  index = index1[((inputChar & mask1) >> shift)] + (inputChar & mask2);

   138 

   139                  if (index < 7500)

   140                    theChars = index2;

   141                  else

   142                    if (index < 15000) {

   143                      index = index - 7500;

   144                      theChars = index2a;

   145                    }

   146                    else

   147                      if (index < 22500){

   148                        index = index - 15000;

   149                        theChars = index2b;

   150                      }

   151                      else {

   152                        index = index - 22500;

   153                        theChars = index2c;

   154                      }

   155 

   156                  aChar = theChars.charAt(2*index);

   157                  outputByte[0] = (byte)((aChar & 0xff00)>>8);

   158                  outputByte[1] = (byte)(aChar & 0x00ff);

   159                  aChar = theChars.charAt(2*index + 1);

   160                  outputByte[2] = (byte)((aChar & 0xff00)>>8);

   161                  outputByte[3] = (byte)(aChar & 0x00ff);

   162               }

   163 

   164            // if there was no mapping - look for substitution characters

   165 

   166            for (i = 0; i < outputByte.length; i++) {

   167              if (outputByte[i] != 0x00) {

   168                allZeroes = false;

   169                break;

   170              }

   171            }

   172 

   173            if (allZeroes && inputChar != '\u0000')

   174            {

   175               if (subMode) {

   176                  outputByte = subBytes;

   177               } else {

   178                 badInputLength = 1;

   179                 throw new UnknownCharacterException();

   180               }

   181            }

   182 

   183            int oindex = 0;

   184            for (spaceNeeded = outputByte.length; spaceNeeded > 1; spaceNeeded--){

   185              if (outputByte[oindex++] != 0x00 )

   186                break;

   187            }

   188 

   189            if (byteOff + spaceNeeded > outEnd)

   190               throw new ConversionBufferFullException();

   191 

   192 

   193            for (i = outputByte.length - spaceNeeded; i < outputByte.length; i++) {

   194               output[byteOff++] = outputByte[i];

   195            }

   196 

   197            charOff += inputSize;

   198         }

   199 

   200         return byteOff - outOff;

   201     }

   202 

   203     /**

   204      * Resets converter to its initial state.

   205      */

   206     public void reset() {

   207        charOff = byteOff = 0;

   208        highHalfZoneCode = 0;

   209     }

   210 

   211     /**

   212      * Returns the maximum number of bytes needed to convert a char.

   213      */

   214     public int getMaxBytesPerChar() {

   215         return 2;

   216     }

   217 

   218 

   219     /**

   220      * Returns true if the given character can be converted to the

   221      * target character encoding.

   222      */

   223     public boolean canConvert(char ch) {

   224        int    index;

   225        String theChars;

   226 

   227        index = index1[((ch & mask1) >> shift)] + (ch & mask2);

   228 

   229        if (index < 7500)

   230          theChars = index2;

   231        else

   232          if (index < 15000) {

   233            index = index - 7500;

   234            theChars = index2a;

   235          }

   236          else

   237            if (index < 22500){

   238              index = index - 15000;

   239              theChars = index2b;

   240            }

   241            else {

   242              index = index - 22500;

   243              theChars = index2c;

   244            }

   245 

   246        if (theChars.charAt(2*index) != '\u0000' ||

   247                     theChars.charAt(2*index + 1) != '\u0000')

   248          return (true);

   249 

   250        // only return true if input char was unicode null - all others are

   251        //     undefined

   252        return( ch == '\u0000');

   253 

   254     }

   255 

   256 }