1 /*
2 * Copyright (c) 2000, 2017, 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 public US_ASCII() {
40 super("US-ASCII", StandardCharsets.aliases_US_ASCII());
41 }
42
43 public String historicalName() {
44 return "ASCII";
45 }
46
47 public boolean contains(Charset cs) {
48 return (cs instanceof US_ASCII);
49 }
50
51 public CharsetDecoder newDecoder() {
52 return new Decoder(this);
53 }
54
55 public CharsetEncoder newEncoder() {
56 return new Encoder(this);
57 }
58
59 private static class Decoder extends CharsetDecoder {
60
61 private Decoder(Charset cs) {
62 super(cs, 1.0f, 1.0f);
63 }
64
65 private CoderResult decodeArrayLoop(ByteBuffer src,
66 CharBuffer dst)
67 {
68 byte[] sa = src.array();
69 int sp = src.arrayOffset() + src.position();
70 int sl = src.arrayOffset() + src.limit();
71 assert (sp <= sl);
72 sp = (sp <= sl ? sp : sl);
73 char[] da = dst.array();
74 int dp = dst.arrayOffset() + dst.position();
75 int dl = dst.arrayOffset() + dst.limit();
76 assert (dp <= dl);
77 dp = (dp <= dl ? dp : dl);
78
79 try {
80 while (sp < sl) {
81 byte b = sa[sp];
82 if (b >= 0) {
83 if (dp >= dl)
84 return CoderResult.OVERFLOW;
85 da[dp++] = (char)b;
86 sp++;
87 continue;
88 }
89 return CoderResult.malformedForLength(1);
90 }
91 return CoderResult.UNDERFLOW;
92 } finally {
93 src.position(sp - src.arrayOffset());
94 dst.position(dp - dst.arrayOffset());
95 }
96 }
97
98 private CoderResult decodeBufferLoop(ByteBuffer src,
99 CharBuffer dst)
100 {
101 int mark = src.position();
102 try {
103 while (src.hasRemaining()) {
104 byte b = src.get();
105 if (b >= 0) {
106 if (!dst.hasRemaining())
107 return CoderResult.OVERFLOW;
108 dst.put((char)b);
109 mark++;
110 continue;
111 }
112 return CoderResult.malformedForLength(1);
113 }
114 return CoderResult.UNDERFLOW;
115 } finally {
116 src.position(mark);
117 }
118 }
119
120 protected CoderResult decodeLoop(ByteBuffer src,
121 CharBuffer dst)
122 {
123 if (src.hasArray() && dst.hasArray())
124 return decodeArrayLoop(src, dst);
125 else
126 return decodeBufferLoop(src, dst);
127 }
128 }
129
130 private static class Encoder extends CharsetEncoder {
131
132 private Encoder(Charset cs) {
133 super(cs, 1.0f, 1.0f);
134 }
135
136 public boolean canEncode(char c) {
137 return c < 0x80;
138 }
139
140 public boolean isLegalReplacement(byte[] repl) {
141 return (repl.length == 1 && repl[0] >= 0) ||
142 super.isLegalReplacement(repl);
143 }
144
145 private final Surrogate.Parser sgp = new Surrogate.Parser();
146 private CoderResult encodeArrayLoop(CharBuffer src,
147 ByteBuffer dst)
148 {
149 char[] sa = src.array();
150 int sp = src.arrayOffset() + src.position();
151 int sl = src.arrayOffset() + src.limit();
152 assert (sp <= sl);
153 sp = (sp <= sl ? sp : sl);
154 byte[] da = dst.array();
155 int dp = dst.arrayOffset() + dst.position();
156 int dl = dst.arrayOffset() + dst.limit();
157 assert (dp <= dl);
158 dp = (dp <= dl ? dp : dl);
159
160 try {
161 while (sp < sl) {
162 char c = sa[sp];
163 if (c < 0x80) {
164 if (dp >= dl)
165 return CoderResult.OVERFLOW;
166 da[dp] = (byte)c;
167 sp++; dp++;
168 continue;
169 }
170 if (sgp.parse(c, sa, sp, sl) < 0)
171 return sgp.error();
172 return sgp.unmappableResult();
173 }
174 return CoderResult.UNDERFLOW;
175 } finally {
176 src.position(sp - src.arrayOffset());
177 dst.position(dp - dst.arrayOffset());
178 }
179 }
180
181 private CoderResult encodeBufferLoop(CharBuffer src,
182 ByteBuffer dst)
183 {
184 int mark = src.position();
185 try {
186 while (src.hasRemaining()) {
187 char c = src.get();
188 if (c < 0x80) {
189 if (!dst.hasRemaining())
190 return CoderResult.OVERFLOW;
191 dst.put((byte)c);
192 mark++;
193 continue;
194 }
195 if (sgp.parse(c, src) < 0)
196 return sgp.error();
197 return sgp.unmappableResult();
198 }
199 return CoderResult.UNDERFLOW;
200 } finally {
201 src.position(mark);
202 }
203 }
204
205 protected CoderResult encodeLoop(CharBuffer src,
206 ByteBuffer dst)
207 {
208 if (src.hasArray() && dst.hasArray())
209 return encodeArrayLoop(src, dst);
210 else
211 return encodeBufferLoop(src, dst);
212 }
213
214 }
215 }