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 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, 0, 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, 0, 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) {
73        return toString(ba, ba.length);
74    }
75
76    byte[] getBytes(String s) {
77        CharsetEncoder ce = encoder().reset();
78        char[] ca = s.toCharArray();
79        int len = (int)(ca.length * ce.maxBytesPerChar());
80        byte[] ba = new byte[len];
81        if (len == 0)
82            return ba;
83        // UTF-8 only for now. Other ArrayDeocder only handles
84        // CodingErrorAction.REPLACE mode.
85        if (isUTF8 && ce instanceof ArrayEncoder) {
86            int blen = ((ArrayEncoder)ce).encode(ca, 0, ca.length, ba);
87            if (blen == -1)    // malformed
88                throw new IllegalArgumentException("MALFORMED");
89            return Arrays.copyOf(ba, blen);
90        }
91        ByteBuffer bb = ByteBuffer.wrap(ba);
92        CharBuffer cb = CharBuffer.wrap(ca);
93        CoderResult cr = ce.encode(cb, bb, true);
94        if (!cr.isUnderflow())
95            throw new IllegalArgumentException(cr.toString());
96        cr = ce.flush(bb);
97        if (!cr.isUnderflow())
98            throw new IllegalArgumentException(cr.toString());
99        if (bb.position() == ba.length)  // defensive copy?
100            return ba;
101        else
102            return Arrays.copyOf(ba, bb.position());
103    }
104
105    // assume invoked only if "this" is not utf8
106    byte[] getBytesUTF8(String s) {
107        if (isUTF8)
108            return getBytes(s);
109        if (utf8 == null)
110            utf8 = new ZipCoder(StandardCharsets.UTF_8);
111        return utf8.getBytes(s);
112    }
113
114
115    String toStringUTF8(byte[] ba, int len) {
116        if (isUTF8)
117            return toString(ba, len);
118        if (utf8 == null)
119            utf8 = new ZipCoder(StandardCharsets.UTF_8);
120        return utf8.toString(ba, len);
121    }
122
123    boolean isUTF8() {
124        return isUTF8;
125    }
126
127    private Charset cs;
128    private CharsetDecoder dec;
129    private CharsetEncoder enc;
130    private boolean isUTF8;
131    private ZipCoder utf8;
132
133    private ZipCoder(Charset cs) {
134        this.cs = cs;
135        this.isUTF8 = cs.name().equals(StandardCharsets.UTF_8.name());
136    }
137
138    static ZipCoder get(Charset charset) {
139        return new ZipCoder(charset);
140    }
141
142    private CharsetDecoder decoder() {
143        if (dec == null) {
144            dec = cs.newDecoder()
145              .onMalformedInput(CodingErrorAction.REPORT)
146              .onUnmappableCharacter(CodingErrorAction.REPORT);
147        }
148        return dec;
149    }
150
151    private CharsetEncoder encoder() {
152        if (enc == null) {
153            enc = cs.newEncoder()
154              .onMalformedInput(CodingErrorAction.REPORT)
155              .onUnmappableCharacter(CodingErrorAction.REPORT);
156        }
157        return enc;
158    }
159}
160