1/*
2 * Copyright (c) 2000, 2012, 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
30import java.nio.ByteBuffer;
31import java.nio.CharBuffer;
32import java.nio.charset.Charset;
33import java.nio.charset.CharsetDecoder;
34import java.nio.charset.CoderResult;
35import java.nio.charset.CharacterCodingException;
36import java.nio.charset.MalformedInputException;
37import java.nio.charset.UnmappableCharacterException;
38
39
40public abstract class SingleByteDecoder
41    extends CharsetDecoder
42{
43
44    private final String byteToCharTable;
45
46    protected SingleByteDecoder(Charset cs, String byteToCharTable) {
47        super(cs, 1.0f, 1.0f);
48        this.byteToCharTable = byteToCharTable;
49    }
50
51    private CoderResult decodeArrayLoop(ByteBuffer src, CharBuffer dst) {
52        byte[] sa = src.array();
53        int sp = src.arrayOffset() + src.position();
54        int sl = src.arrayOffset() + src.limit();
55        assert (sp <= sl);
56        sp = (sp <= sl ? sp : sl);
57        char[] da = dst.array();
58        int dp = dst.arrayOffset() + dst.position();
59        int dl = dst.arrayOffset() + dst.limit();
60        assert (dp <= dl);
61        dp = (dp <= dl ? dp : dl);
62
63        try {
64            while (sp < sl) {
65                int b = sa[sp];
66
67                char c = decode(b);
68                if (c == '\uFFFD')
69                    return CoderResult.unmappableForLength(1);
70                if (dl - dp < 1)
71                    return CoderResult.OVERFLOW;
72                da[dp++] = c;
73                sp++;
74            }
75            return CoderResult.UNDERFLOW;
76        } finally {
77            src.position(sp - src.arrayOffset());
78            dst.position(dp - dst.arrayOffset());
79        }
80    }
81
82    private CoderResult decodeBufferLoop(ByteBuffer src, CharBuffer dst) {
83        int mark = src.position();
84        try {
85            while (src.hasRemaining()) {
86                int b = src.get();
87
88                char c = decode(b);
89                if (c == '\uFFFD')
90                    return CoderResult.unmappableForLength(1);
91                if (!dst.hasRemaining())
92                    return CoderResult.OVERFLOW;
93                mark++;
94                dst.put(c);
95            }
96            return CoderResult.UNDERFLOW;
97        } finally {
98            src.position(mark);
99        }
100    }
101
102    protected CoderResult decodeLoop(ByteBuffer src, CharBuffer dst) {
103        if (true && src.hasArray() && dst.hasArray())
104            return decodeArrayLoop(src, dst);
105        else
106            return decodeBufferLoop(src, dst);
107    }
108
109    public char decode(int byteIndex) {
110        int n = byteIndex + 128;
111        if (n >= byteToCharTable.length() || n < 0)
112            return '\uFFFD';
113        return byteToCharTable.charAt(n);
114    }
115}
116