1 /*
2 * Copyright 1996-2003 Sun Microsystems, Inc. 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. Sun designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
22 * CA 95054 USA or visit www.sun.com if you need additional information or
23 * have any questions.
24 */
25
26 package sun.io;
27
28 import sun.nio.cs.ext.EUC_TW;
29
30 /*
31 * @author Limin Shi
32 */
33
34 public class CharToByteEUC_TW extends CharToByteConverter
35 {
36 private final byte MSB = (byte)0x80;
37 private final byte SS2 = (byte) 0x8E;
38 private final byte P2 = (byte) 0xA2;
39 private final byte P3 = (byte) 0xA3;
40
41 private final static EUC_TW nioCoder = new EUC_TW();
42
43 private static String uniTab1 = nioCoder.getUniTab1();
44 private static String uniTab2 = nioCoder.getUniTab2();
45 private static String uniTab3 = nioCoder.getUniTab3();
46 private static String cnsTab1 = nioCoder.getCNSTab1();
47 private static String cnsTab2 = nioCoder.getCNSTab2();
48 private static String cnsTab3 = nioCoder.getCNSTab3();
49
50 public int flush(byte[] output, int outStart, int outEnd)
51 throws MalformedInputException
52 {
53 reset();
54 return 0;
55 }
56
57 public void reset() {
58 byteOff = charOff = 0;
59 }
60
61 public boolean canConvert(char ch){
62 if (((0xFF00 & ch) != 0) && (getNative(ch) != -1)){
63 return true;
64 }
65 return false;
66 }
67
68 /**
69 * Character conversion
70 */
71 public int convert(char[] input, int inOff, int inEnd,
72 byte[] output, int outOff, int outEnd)
73 throws UnknownCharacterException, MalformedInputException,
74 ConversionBufferFullException
75 {
76 int outputSize;
77 byte [] tmpbuf = new byte[4];
78 byte [] outputByte;
79
80 byteOff = outOff;
81
82 //Fixed 4122961 by bringing the charOff++ out to this
83 // loop where it belongs, changing the loop from
84 // while(){} to for(){}.
85 for (charOff = inOff; charOff < inEnd; charOff++) {
86 outputByte = tmpbuf;
87 if ( input[charOff] < 0x80) { // ASCII
88 outputSize = 1;
89 outputByte[0] = (byte)(input[charOff] & 0x7f);
90 } else {
91 outputSize = unicodeToEUC(input[charOff], outputByte);
92 }
93
94 if (outputSize == -1) {
95 if (subMode) {
96 outputByte = subBytes;
97 outputSize = subBytes.length;
98 } else {
99 badInputLength = 1;
100 throw new UnknownCharacterException();
101 }
102 }
103
104 if (outEnd - byteOff < outputSize)
105 throw new ConversionBufferFullException();
106
107 for (int i = 0; i < outputSize; i++)
108 output[byteOff++] = outputByte[i];
109 }
110
111 return byteOff - outOff;
112
113 }
114
115
116 /**
117 * returns the maximum number of bytes needed to convert a char
118 */
119 public int getMaxBytesPerChar() {
120 return 4;
121 }
122
123
124 /**
125 * Return the character set ID
126 */
127 public String getCharacterEncoding() {
128 return "EUC_TW";
129 }
130
131
132 protected int getNative(char unicode) {
133 int i,
134 cns; // 2 chars in CNS table make 1 CNS code
135
136 if (unicode < UniTab2[0]) {
137 if ((i = searchTab(unicode, UniTab1)) == -1)
138 return -1;
139 cns = (CNSTab1[2*i] << 16) + CNSTab1[2*i+1];
140 return cns;
141 } else if (unicode < UniTab3[0]) {
142 if ((i = searchTab(unicode, UniTab2)) == -1)
143 return -1;
144 cns = (CNSTab2[2*i] << 16) + CNSTab2[2*i+1];
145 return cns;
146 } else {
147 if ((i = searchTab(unicode, UniTab3)) == -1)
148 return -1;
149 cns = (CNSTab3[2*i] << 16) + CNSTab3[2*i+1];
150 return cns;
151 }
152 }
153
154 protected int searchTab(char code, char [] table) {
155 int i = 0, l, h;
156
157 for (l = 0, h = table.length - 1; l < h; ) {
158 if (table[l] == code) {
159 i = l;
160 break;
161 }
162 if (table[h] == code) {
163 i = h;
164 break;
165 }
166 i = (l + h) / 2;
167 if (table[i] == code)
168 break;
169 if (table[i] < code)
170 l = i + 1;
171 else h = i - 1;
172 }
173 if (code == table[i]) {
174 return i;
175 } else {
176 return -1;
177 }
178 }
179
180
181 private int unicodeToEUC(char unicode, byte ebyte[]) {
182 int cns = getNative(unicode);
183
184 if ((cns >> 16) == 0x01) { // Plane 1
185 ebyte[0] = (byte) (((cns & 0xff00) >> 8) | MSB);
186 ebyte[1] = (byte) ((cns & 0xff) | MSB);
187 return 2;
188 }
189
190 byte cnsPlane = (byte)(cns >> 16);
191 if (cnsPlane >= (byte)0x02) { // Plane 2
192 ebyte[0] = SS2;
193 ebyte[1] = (byte) (cnsPlane | (byte)0xA0);
194 ebyte[2] = (byte) (((cns & 0xff00) >> 8) | MSB);
195 ebyte[3] = (byte) ((cns & 0xff) | MSB);
196 return 4;
197 }
198
199 return -1;
200 }
201
202 protected int unicodeToEUC(char unicode) {
203 if (unicode <= 0x7F) { // ASCII falls into EUC_TW CS0
204 return unicode;
205 }
206
207 int cns = getNative(unicode);
208 int plane = cns >> 16;
209 int euc = (cns & 0x0000FFFF) | 0x00008080;
210
211 if (plane == 1) {
212 return euc;
213 } else if (plane == 2) {
214 return ((SS2 << 24) & 0xFF000000) | ((P2 << 16) & 0x00FF0000) |
215 euc;
216 } else if (plane == 3) {
217 return ((SS2 << 24) & 0xFF000000) | ((P3 << 16) & 0x00FF0000) |
218 euc;
219 }
220
221 return -1;
222 }
223
224 private char [] UniTab1 = uniTab1.toCharArray();
225 private char [] UniTab2 = uniTab2.toCharArray();
226 private char [] UniTab3 = uniTab3.toCharArray();
227 private char [] CNSTab1 = cnsTab1.toCharArray();
228 private char [] CNSTab2 = cnsTab2.toCharArray();
229 private char [] CNSTab3 = cnsTab3.toCharArray();
230 }