1/*
2 * Copyright (c) 2009, 2011, 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
26package java.util.zip;
27
28import java.nio.ByteBuffer;
29import java.nio.CharBuffer;
30import java.nio.charset.Charset;
31import java.nio.charset.StandardCharsets;
32import java.nio.charset.CharsetDecoder;
33import java.nio.charset.CharsetEncoder;
34import java.nio.charset.CoderResult;
35import java.nio.charset.CodingErrorAction;
36import java.util.Arrays;
37import sun.nio.cs.ArrayDecoder;
38import sun.nio.cs.ArrayEncoder;
39
40/**
41 * Utility class for zipfile name and comment decoding and encoding
42 */
43
44final class ZipCoder {
45
46    String toString(byte[] ba, int off, int length) {
47        CharsetDecoder cd = decoder().reset();
48        int len = (int)(length * cd.maxCharsPerByte());
49        char[] ca = new char[len];
50        if (len == 0)
51            return new String(ca);
52        // UTF-8 only for now. Other ArrayDeocder only handles
53        // CodingErrorAction.REPLACE mode. ZipCoder uses
54        // REPORT mode.
55        if (isUTF8 && cd instanceof ArrayDecoder) {
56            int clen = ((ArrayDecoder)cd).decode(ba, off, length, ca);
57            if (clen == -1)    // malformed
58                throw new IllegalArgumentException("MALFORMED");
59            return new String(ca, 0, clen);
60        }
61        ByteBuffer bb = ByteBuffer.wrap(ba, off, length);
62        CharBuffer cb = CharBuffer.wrap(ca);
63        CoderResult cr = cd.decode(bb, cb, true);
64        if (!cr.isUnderflow())
65            throw new IllegalArgumentException(cr.toString());
66        cr = cd.flush(cb);
67        if (!cr.isUnderflow())
68            throw new IllegalArgumentException(cr.toString());
69        return new String(ca, 0, cb.position());
70    }
71
72    String toString(byte[] ba, int length) {
73        return toString(ba, 0, length);
74    }
75
76    String toString(byte[] ba) {
77        return toString(ba, 0, ba.length);
78    }
79
80    byte[] getBytes(String s) {
81        CharsetEncoder ce = encoder().reset();
82        char[] ca = s.toCharArray();
83        int len = (int)(ca.length * ce.maxBytesPerChar());
84        byte[] ba = new byte[len];
85        if (len == 0)
86            return ba;
87        // UTF-8 only for now. Other ArrayDeocder only handles
88        // CodingErrorAction.REPLACE mode.
89        if (isUTF8 && ce instanceof ArrayEncoder) {
90            int blen = ((ArrayEncoder)ce).encode(ca, 0, ca.length, ba);
91            if (blen == -1)    // malformed
92                throw new IllegalArgumentException("MALFORMED");
93            return Arrays.copyOf(ba, blen);
94        }
95        ByteBuffer bb = ByteBuffer.wrap(ba);
96        CharBuffer cb = CharBuffer.wrap(ca);
97        CoderResult cr = ce.encode(cb, bb, true);
98        if (!cr.isUnderflow())
99            throw new IllegalArgumentException(cr.toString());
100        cr = ce.flush(bb);
101        if (!cr.isUnderflow())
102            throw new IllegalArgumentException(cr.toString());
103        if (bb.position() == ba.length)  // defensive copy?
104            return ba;
105        else
106            return Arrays.copyOf(ba, bb.position());
107    }
108
109    // assume invoked only if "this" is not utf8
110    byte[] getBytesUTF8(String s) {
111        if (isUTF8)
112            return getBytes(s);
113        if (utf8 == null)
114            utf8 = new ZipCoder(StandardCharsets.UTF_8);
115        return utf8.getBytes(s);
116    }
117
118    String toStringUTF8(byte[] ba, int len) {
119        return toStringUTF8(ba, 0, len);
120    }
121
122    String toStringUTF8(byte[] ba, int off, int len) {
123        if (isUTF8)
124            return toString(ba, off, len);
125        if (utf8 == null)
126            utf8 = new ZipCoder(StandardCharsets.UTF_8);
127        return utf8.toString(ba, off, len);
128    }
129
130    boolean isUTF8() {
131        return isUTF8;
132    }
133
134    private Charset cs;
135    private CharsetDecoder dec;
136    private CharsetEncoder enc;
137    private boolean isUTF8;
138    private ZipCoder utf8;
139
140    private ZipCoder(Charset cs) {
141        this.cs = cs;
142        this.isUTF8 = cs.name().equals(StandardCharsets.UTF_8.name());
143    }
144
145    static ZipCoder get(Charset charset) {
146        return new ZipCoder(charset);
147    }
148
149    private CharsetDecoder decoder() {
150        if (dec == null) {
151            dec = cs.newDecoder()
152              .onMalformedInput(CodingErrorAction.REPORT)
153              .onUnmappableCharacter(CodingErrorAction.REPORT);
154        }
155        return dec;
156    }
157
158    private CharsetEncoder encoder() {
159        if (enc == null) {
160            enc = cs.newEncoder()
161              .onMalformedInput(CodingErrorAction.REPORT)
162              .onUnmappableCharacter(CodingErrorAction.REPORT);
163        }
164        return enc;
165    }
166}
167