1/*
2 * Copyright (C) 2007 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.dx.dex.file;
18
19import com.android.dx.rop.cst.CstString;
20import com.android.dx.util.AnnotatedOutput;
21import com.android.dx.util.ByteArray;
22import com.android.dx.util.Hex;
23import com.android.dx.util.Leb128Utils;
24
25/**
26 * Representation of string data for a particular string, in a Dalvik file.
27 */
28public final class StringDataItem extends OffsettedItem {
29    /** {@code non-null;} the string value */
30    private final CstString value;
31
32    /**
33     * Constructs an instance.
34     *
35     * @param value {@code non-null;} the string value
36     */
37    public StringDataItem(CstString value) {
38        super(1, writeSize(value));
39
40        this.value = value;
41    }
42
43    /**
44     * Gets the write size for a given value.
45     *
46     * @param value {@code non-null;} the string value
47     * @return {@code >= 2}; the write size, in bytes
48     */
49    private static int writeSize(CstString value) {
50        int utf16Size = value.getUtf16Size();
51
52        // The +1 is for the '\0' termination byte.
53        return Leb128Utils.unsignedLeb128Size(utf16Size)
54            + value.getUtf8Size() + 1;
55    }
56
57    /** {@inheritDoc} */
58    @Override
59    public ItemType itemType() {
60        return ItemType.TYPE_STRING_DATA_ITEM;
61    }
62
63    /** {@inheritDoc} */
64    @Override
65    public void addContents(DexFile file) {
66        // Nothing to do here.
67    }
68
69    /** {@inheritDoc} */
70    @Override
71    public void writeTo0(DexFile file, AnnotatedOutput out) {
72        ByteArray bytes = value.getBytes();
73        int utf16Size = value.getUtf16Size();
74
75        if (out.annotates()) {
76            out.annotate(Leb128Utils.unsignedLeb128Size(utf16Size),
77                    "utf16_size: " + Hex.u4(utf16Size));
78            out.annotate(bytes.size() + 1, value.toQuoted());
79        }
80
81        out.writeUleb128(utf16Size);
82        out.write(bytes);
83        out.writeByte(0);
84    }
85
86    /** {@inheritDoc} */
87    @Override
88    public String toHuman() {
89        return value.toQuoted();
90    }
91
92    /** {@inheritDoc} */
93    @Override
94    protected int compareTo0(OffsettedItem other) {
95        StringDataItem otherData = (StringDataItem) other;
96
97        return value.compareTo(otherData.value);
98    }
99}
100