1 /*
2 * Copyright (c) 2000, 2004, 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.nio.cs;
27
28 import java.nio.ByteBuffer;
29 import java.nio.CharBuffer;
30 import java.nio.charset.Charset;
31 import java.nio.charset.CharsetDecoder;
32 import java.nio.charset.CharsetEncoder;
33 import java.nio.charset.CoderResult;
34
35 public class US_ASCII
36 extends Charset
37 implements HistoricallyNamedCharset
38 {
39
40 public US_ASCII() {
41 super("US-ASCII", StandardCharsets.aliases_US_ASCII);
42 }
43
44 public String historicalName() {
45 return "ASCII";
46 }
47
48 public boolean contains(Charset cs) {
49 return (cs instanceof US_ASCII);
50 }
51
52 public CharsetDecoder newDecoder() {
53 return new Decoder(this);
54 }
55
56 public CharsetEncoder newEncoder() {
57 return new Encoder(this);
58 }
59
60 private static class Decoder extends CharsetDecoder
61 implements ArrayDecoder {
62
63 private Decoder(Charset cs) {
64 super(cs, 1.0f, 1.0f);
65 }
66
67 private CoderResult decodeArrayLoop(ByteBuffer src,
68 CharBuffer dst)
69 {
70 byte[] sa = src.array();
71 int sp = src.arrayOffset() + src.position();
72 int sl = src.arrayOffset() + src.limit();
73 assert (sp <= sl);
74 sp = (sp <= sl ? sp : sl);
75 char[] da = dst.array();
76 int dp = dst.arrayOffset() + dst.position();
77 int dl = dst.arrayOffset() + dst.limit();
78 assert (dp <= dl);
79 dp = (dp <= dl ? dp : dl);
80
81 try {
82 while (sp < sl) {
83 byte b = sa[sp];
84 if (b >= 0) {
85 if (dp >= dl)
86 return CoderResult.OVERFLOW;
87 da[dp++] = (char)b;
88 sp++;
89 continue;
90 }
91 return CoderResult.malformedForLength(1);
92 }
93 return CoderResult.UNDERFLOW;
94 } finally {
95 src.position(sp - src.arrayOffset());
96 dst.position(dp - dst.arrayOffset());
97 }
98 }
99
100 private CoderResult decodeBufferLoop(ByteBuffer src,
101 CharBuffer dst)
102 {
103 int mark = src.position();
104 try {
105 while (src.hasRemaining()) {
106 byte b = src.get();
107 if (b >= 0) {
108 if (!dst.hasRemaining())
109 return CoderResult.OVERFLOW;
110 dst.put((char)b);
111 mark++;
112 continue;
113 }
114 return CoderResult.malformedForLength(1);
115 }
116 return CoderResult.UNDERFLOW;
117 } finally {
118 src.position(mark);
119 }
120 }
121
122 protected CoderResult decodeLoop(ByteBuffer src,
123 CharBuffer dst)
124 {
125 if (src.hasArray() && dst.hasArray())
126 return decodeArrayLoop(src, dst);
127 else
128 return decodeBufferLoop(src, dst);
129 }
130
131 private char repl = '\uFFFD';
132 protected void implReplaceWith(String newReplacement) {
133 repl = newReplacement.charAt(0);
134 }
135
136 public int decode(byte[] src, int sp, int len, char[] dst) {
137 int dp = 0;
138 len = Math.min(len, dst.length);
139 while (dp < len) {
140 byte b = src[sp++];
141 if (b >= 0)
142 dst[dp++] = (char)b;
143 else
144 dst[dp++] = repl;
145 }
146 return dp;
147 }
148
149 public boolean isASCIICompatible() {
150 return true;
151 }
152 }
153
154 private static class Encoder extends CharsetEncoder
155 implements ArrayEncoder {
156
157 private Encoder(Charset cs) {
158 super(cs, 1.0f, 1.0f);
159 }
160
161 public boolean canEncode(char c) {
162 return c < 0x80;
163 }
164
165 public boolean isLegalReplacement(byte[] repl) {
166 return (repl.length == 1 && repl[0] >= 0) ||
167 super.isLegalReplacement(repl);
168 }
169
170 private final Surrogate.Parser sgp = new Surrogate.Parser();
171 private CoderResult encodeArrayLoop(CharBuffer src,
172 ByteBuffer dst)
173 {
174 char[] sa = src.array();
175 int sp = src.arrayOffset() + src.position();
176 int sl = src.arrayOffset() + src.limit();
177 assert (sp <= sl);
178 sp = (sp <= sl ? sp : sl);
179 byte[] da = dst.array();
180 int dp = dst.arrayOffset() + dst.position();
181 int dl = dst.arrayOffset() + dst.limit();
182 assert (dp <= dl);
183 dp = (dp <= dl ? dp : dl);
184
185 try {
186 while (sp < sl) {
187 char c = sa[sp];
188 if (c < 0x80) {
189 if (dp >= dl)
190 return CoderResult.OVERFLOW;
191 da[dp] = (byte)c;
192 sp++; dp++;
193 continue;
194 }
195 if (sgp.parse(c, sa, sp, sl) < 0)
196 return sgp.error();
197 return sgp.unmappableResult();
198 }
199 return CoderResult.UNDERFLOW;
200 } finally {
201 src.position(sp - src.arrayOffset());
202 dst.position(dp - dst.arrayOffset());
203 }
204 }
205
206 private CoderResult encodeBufferLoop(CharBuffer src,
207 ByteBuffer dst)
208 {
209 int mark = src.position();
210 try {
211 while (src.hasRemaining()) {
212 char c = src.get();
213 if (c < 0x80) {
214 if (!dst.hasRemaining())
215 return CoderResult.OVERFLOW;
216 dst.put((byte)c);
217 mark++;
218 continue;
219 }
220 if (sgp.parse(c, src) < 0)
221 return sgp.error();
222 return sgp.unmappableResult();
223 }
224 return CoderResult.UNDERFLOW;
225 } finally {
226 src.position(mark);
227 }
228 }
229
230 protected CoderResult encodeLoop(CharBuffer src,
231 ByteBuffer dst)
232 {
233 if (src.hasArray() && dst.hasArray())
234 return encodeArrayLoop(src, dst);
235 else
236 return encodeBufferLoop(src, dst);
237 }
238
239 private byte repl = (byte)'?';
240 protected void implReplaceWith(byte[] newReplacement) {
241 repl = newReplacement[0];
242 }
243
244 public int encode(char[] src, int sp, int len, byte[] dst) {
245 int dp = 0;
246 int sl = sp + Math.min(len, dst.length);
247 while (sp < sl) {
248 char c = src[sp++];
249 if (c < 0x80) {
250 dst[dp++] = (byte)c;
251 continue;
252 }
253 if (Character.isHighSurrogate(c) && sp < sl &&
254 Character.isLowSurrogate(src[sp])) {
255 if (len > dst.length) {
256 sl++;
257 len--;
258 }
259 sp++;
260 }
261 dst[dp++] = repl;
262 }
263 return dp;
264 }
265
266 public boolean isASCIICompatible() {
267 return true;
268 }
269 }
270
271 }