1 /*

     2  * Copyright (c) 1999, 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 

    26 package sun.io;

    27 

    28 import sun.nio.cs.ext.ISCII91;

    29 

    30 /*

    31  * Copyright (c) 1998 International Business Machines.

    32  * All Rights Reserved.

    33  *

    34  * Author : Sunanda Bera, C. Thirumalesh

    35  * Last Modified : 11,December,1998

    36  *

    37  * Purpose : Defines class CharToByteISCII91.

    38  *

    39  *

    40  * Revision History

    41  * ======== =======

    42  *

    43  * Date        By            Description

    44  * ----        --            -----------

    45  * March 29, 1999 John Raley Removed MalformedInputException; modified substitution logic

    46  *

    47  */

    48 

    49 /**

    50  * Converter class. Converts between ISCII91 encoding and Unicode encoding.

    51  * ISCII91 is the character encoding as defined in Indian Standard document

    52  * IS 13194:1991 ( Indian Script Code for Information Interchange ).

    53  *

    54  * @see sun.io.CharToByteConverter

    55  */

    56 

    57 /*

    58  * {jbr} I am not sure this class adheres to code converter conventions.

    59  * Need to investigate.

    60  * Might should recode as a subclass of CharToByteSingleByte.

    61  */

    62 

    63 public class CharToByteISCII91 extends CharToByteConverter {

    64 

    65         private static final byte NO_CHAR = (byte)255;

    66 

    67         //private final static ISCII91 nioCoder = new ISCII91();

    68         private final static byte[] directMapTable = ISCII91.getEncoderMappingTable();

    69 

    70         private static final char NUKTA_CHAR = '\u093c';

    71         private static final char HALANT_CHAR = '\u094d';

    72 

    73 

    74 /**

    75  * @return true for Devanagari and ASCII range and for the special characters

    76  *              Zero Width Joiner and Zero Width Non-Joiner

    77  * @see sun.io.CharToByteConverter#canConvert

    78  *

    79  */

    80         public boolean canConvert(char ch) {

    81         //check for Devanagari range,ZWJ,ZWNJ and ASCII range.

    82         return ((ch >= 0x0900 && ch <= 0x097f) || (ch == 0x200d || ch == 0x200c)

    83                                 || (ch >= 0x0000 && ch <= 0x007f) );

    84         } //canConvert()

    85 /**

    86  * Converts both Devanagari and ASCII range of characters.

    87  * @see sun.io.CharToByteConverter#convert

    88  */

    89     public int convert(char[] input, int inStart, int inEnd, byte[] output, int outStart, int outEnd) throws MalformedInputException, UnknownCharacterException, ConversionBufferFullException {

    90 

    91         charOff = inStart;

    92         byteOff = outStart;

    93 

    94         for (;charOff < inEnd; charOff++) {

    95 

    96             char inputChar = input[charOff];

    97             int index = Integer.MIN_VALUE;

    98             boolean isSurrogatePair = false;

    99 

   100             //check if input is in ASCII RANGE

   101             if (inputChar >= 0x0000 && inputChar <= 0x007f) {

   102                 if (byteOff >= outEnd) {

   103                         throw new ConversionBufferFullException();

   104                 }

   105                 output[byteOff++] = (byte) inputChar;

   106                 continue;

   107             }

   108 

   109             // if inputChar == ZWJ replace it with halant

   110             // if inputChar == ZWNJ replace it with Nukta

   111             if (inputChar == 0x200c) {

   112                 inputChar = HALANT_CHAR;

   113             }

   114             else if (inputChar == 0x200d) {

   115                 inputChar = NUKTA_CHAR;

   116             }

   117 

   118             if (inputChar >= 0x0900 && inputChar <= 0x097f) {

   119                 index = ((int)(inputChar) - 0x0900)*2;

   120             }

   121 

   122             // If input char is a high surrogate, ensure that the following

   123             // char is a low surrogate.  If not, throw a MalformedInputException.

   124             // Leave index untouched so substitution or an UnknownCharacterException

   125             // will result.

   126             else if (inputChar >= 0xd800 && inputChar <= 0xdbff) {

   127                 if (charOff < inEnd-1) {

   128                     char nextChar = input[charOff];

   129                     if (nextChar >= 0xdc00 && nextChar <= 0xdfff) {

   130                         charOff++;

   131                         isSurrogatePair = true;

   132                     }

   133                 }

   134                 if (!isSurrogatePair) {

   135                     badInputLength = 1;

   136                     throw new MalformedInputException();

   137                 }

   138             }

   139             else if (inputChar >= 0xdc00 && inputChar <= 0xdfff) {

   140                 badInputLength = 1;

   141                 throw new MalformedInputException();

   142             }

   143 

   144             if (index == Integer.MIN_VALUE || directMapTable[index] == NO_CHAR) {

   145                 if (subMode) {

   146                     if (byteOff + subBytes.length >= outEnd) {

   147                             throw new ConversionBufferFullException();

   148                     }

   149                     System.arraycopy(subBytes, 0, output, byteOff, subBytes.length);

   150                     byteOff += subBytes.length;

   151                 } else {

   152                     badInputLength = isSurrogatePair? 2 : 1;

   153                     throw new UnknownCharacterException();

   154                 }

   155             }

   156             else {

   157                 if(byteOff >= outEnd) {

   158                     throw new ConversionBufferFullException();

   159                 }

   160                 output[byteOff++] = directMapTable[index++];

   161                 if(directMapTable[index] != NO_CHAR) {

   162                     if(byteOff >= outEnd) {

   163                             throw new ConversionBufferFullException();

   164                     }

   165                     output[byteOff++] = directMapTable[index];

   166                 }

   167             }

   168 

   169         } //end for

   170 

   171         return byteOff - outStart;

   172     } //end of routine convert.

   173 

   174 /**

   175 * @see sun.io.CharToByteConverter#flush

   176 */

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

   178         throws MalformedInputException, ConversionBufferFullException {

   179         byteOff = charOff = 0;

   180         return 0;

   181         }//flush()

   182 /**

   183  * @return The character encoding as a String.

   184  */

   185         public String getCharacterEncoding() {

   186         return "ISCII91";

   187         }//getCharacterEncoding

   188 /**

   189  * @see sun.io.CharToByteConverter#getMaxBytesPerChar

   190  */

   191         public int getMaxBytesPerChar() {

   192         return 2;

   193         }//getMaxBytesPerChar()

   194 /**

   195  * @see sun.io.CharToByteConverter#reset

   196  */

   197         public void reset() {

   198         byteOff = charOff = 0;

   199         }

   200 } //end of class definition