1 /*
   2  * Copyright (c) 2002, 2006, 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 /*
  27  */
  28 
  29 package sun.nio.cs.ext;
  30 
  31 import java.nio.charset.Charset;
  32 import java.nio.ByteBuffer;
  33 import java.nio.CharBuffer;
  34 import java.nio.charset.CharsetDecoder;
  35 import java.nio.charset.CharsetEncoder;
  36 import java.nio.charset.CoderResult;
  37 import sun.nio.cs.HistoricallyNamedCharset;
  38 import sun.nio.cs.*;
  39 
  40 public class ISO2022_CN_CNS extends ISO2022 implements HistoricallyNamedCharset
  41 {
  42     public ISO2022_CN_CNS() {
  43         super("x-ISO-2022-CN-CNS", ExtendedCharsets.aliasesFor("x-ISO-2022-CN-CNS"));
  44     }
  45 
  46     public boolean contains(Charset cs) {
  47         // overlapping repertoire of EUC_TW, CNS11643
  48         return ((cs instanceof EUC_TW) ||
  49                 (cs.name().equals("US-ASCII")) ||
  50                 (cs instanceof ISO2022_CN_CNS));
  51     }
  52 
  53     public String historicalName() {
  54         return "ISO2022CN_CNS";
  55     }
  56 
  57     public CharsetDecoder newDecoder() {
  58         return new ISO2022_CN.Decoder(this);
  59     }
  60 
  61     public CharsetEncoder newEncoder() {
  62         return new Encoder(this);
  63     }
  64 
  65     private static class Encoder extends ISO2022.Encoder {
  66 
  67         public Encoder(Charset cs)
  68         {
  69             super(cs);
  70             SODesig =  new byte[] {'$', ')', 'G' };
  71             SS2Desig = new byte[] {'$', '*', 'H' };
  72             SS3Desig = new byte[] {'$', '+', 'I' };
  73 
  74             try {
  75                 Charset cset = Charset.forName("EUC_TW"); // CNS11643
  76                 ISOEncoder = cset.newEncoder();
  77             } catch (Exception e) { }
  78         }
  79 
  80         private byte[] bb = new byte[4];
  81         public boolean canEncode(char c) {
  82             int n = 0;
  83             return (c <= '\u007f' ||
  84                     (n = ((EUC_TW.Encoder)ISOEncoder).toEUC(c, bb)) == 2 ||
  85                     (n == 4 && bb[0] == SS2 &&
  86                      (bb[1] == PLANE2 || bb[1] == PLANE3)));
  87         }
  88 
  89         /*
  90          * Since ISO2022-CN-CNS possesses a CharsetEncoder
  91          * without the corresponding CharsetDecoder half the
  92          * default replacement check needs to be overridden
  93          * since the parent class version attempts to
  94          * decode 0x3f (?).
  95          */
  96 
  97         public boolean isLegalReplacement(byte[] repl) {
  98             // 0x3f is OK as the replacement byte
  99             return (repl.length == 1 && repl[0] == (byte) 0x3f);
 100         }
 101     }
 102 }