1 /*
2 * Copyright 1997 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 package sun.io;
26
27 public abstract class ByteToCharDBCS_EBCDIC extends ByteToCharConverter
28 {
29
30 private static final int SBCS = 0;
31 private static final int DBCS = 1;
32
33 private static final int SO = 0x0e;
34 private static final int SI = 0x0f;
35
36 private int currentState;
37 private boolean savedBytePresent;
38 private byte savedByte;
39
40 protected String singleByteToChar;
41 protected short index1[];
42 protected String index2;
43 protected int mask1;
44 protected int mask2;
45 protected int shift;
46
47
48 public ByteToCharDBCS_EBCDIC() {
49 super();
50 currentState = SBCS;
51 savedBytePresent = false;
52 }
53
54 public int flush(char [] output, int outStart, int outEnd)
55 throws MalformedInputException
56 {
57
58 if (savedBytePresent) {
59 reset();
60 badInputLength = 0;
61 throw new MalformedInputException();
62 }
63
64 reset();
65 return 0;
66 }
67
68 /**
69 * Character conversion
70 */
71 public int convert(byte[] input, int inOff, int inEnd,
72 char[] output, int outOff, int outEnd)
73 throws UnknownCharacterException, MalformedInputException,
74 ConversionBufferFullException
75 {
76 int inputSize;
77 char outputChar = '\uFFFD';
78
79 charOff = outOff;
80 byteOff = inOff;
81
82 while(byteOff < inEnd) {
83 int byte1, byte2;
84 int v;
85
86 if (!savedBytePresent) {
87 byte1 = input[byteOff];
88 inputSize = 1;
89 } else {
90 byte1 = savedByte;
91 savedBytePresent = false;
92 inputSize = 0;
93 }
94
95 if (byte1 == SO) {
96
97 // For SO characters - simply validate the state and if OK
98 // update the state and go to the next byte
99
100 if (currentState != SBCS) {
101 badInputLength = 1;
102 throw new MalformedInputException();
103 } else {
104 currentState = DBCS;
105 byteOff += inputSize;
106 }
107 }
108
109 else
110 if (byte1 == SI) {
111 // For SI characters - simply validate the state and if OK
112 // update the state and go to the next byte
113
114 if (currentState != DBCS) {
115 badInputLength = 1;
116 throw new MalformedInputException();
117 } else {
118 currentState = SBCS;
119 byteOff+= inputSize;
120 }
121 } else {
122
123 // Process the real data characters
124
125 if (byte1 < 0)
126 byte1 += 256;
127
128 if (currentState == SBCS) {
129 outputChar = singleByteToChar.charAt(byte1);
130 } else {
131
132 // for a DBCS character - architecture dictates the
133 // valid range of 1st bytes
134
135 if (byte1 < 0x40 || byte1 > 0xfe) {
136 badInputLength = 1;
137 throw new MalformedInputException();
138 }
139
140 if (byteOff + inputSize >= inEnd) {
141 // We have been split in the middle if a character
142 // save the first byte for next time around
143
144 savedByte = (byte)byte1;
145 savedBytePresent = true;
146 byteOff += inputSize;
147 break;
148 }
149
150 byte2 = input[byteOff+inputSize];
151 if (byte2 < 0)
152 byte2 += 256;
153
154 inputSize++;
155
156 // validate the pair of bytes meet the architecture
157
158 if ((byte1 != 0x40 || byte2 != 0x40) &&
159 (byte2 < 0x41 || byte2 > 0xfe)) {
160 badInputLength = 2;
161 throw new MalformedInputException();
162 }
163
164 // Lookup in the two level index
165 v = byte1 * 256 + byte2;
166 outputChar = index2.charAt(index1[((v & mask1) >> shift)] + (v & mask2));
167 }
168
169 if (outputChar == '\uFFFD') {
170 if (subMode)
171 outputChar = subChars[0];
172 else {
173 badInputLength = inputSize;
174 throw new UnknownCharacterException();
175 }
176 }
177
178 if (charOff >= outEnd)
179 throw new ConversionBufferFullException();
180
181 output[charOff++] = outputChar;
182 byteOff += inputSize;
183 }
184
185 }
186
187 return charOff - outOff;
188 }
189
190
191 /**
192 * Resets the converter.
193 */
194 public void reset() {
195 charOff = byteOff = 0;
196 currentState = SBCS;
197 savedBytePresent = false;
198 }
199 }