1/*
2 * Copyright (C) 2013 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.tools.layoutlib.java;
18
19import java.nio.charset.Charset;
20
21/**
22 * Defines the same class as the java.lang.UnsafeByteSequence which was added in
23 * Dalvik VM. This hack, provides a replacement for that class which can't be
24 * loaded in the standard JVM since it's in the java package and standard JVM
25 * doesn't have it.
26 * <p/>
27 * Extracted from API level 18, file:
28 * platform/libcore/luni/src/main/java/java/lang/UnsafeByteSequence.java
29 */
30public class UnsafeByteSequence {
31    private byte[] bytes;
32    private int count;
33
34    public UnsafeByteSequence(int initialCapacity) {
35        this.bytes = new byte[initialCapacity];
36    }
37
38    public int size() {
39        return count;
40    }
41
42    /**
43     * Moves the write pointer back to the beginning of the sequence,
44     * but without resizing or reallocating the buffer.
45     */
46    public void rewind() {
47        count = 0;
48    }
49
50    public void write(byte[] buffer, int offset, int length) {
51        if (count + length >= bytes.length) {
52            byte[] newBytes = new byte[(count + length) * 2];
53            System.arraycopy(bytes, 0, newBytes, 0, count);
54            bytes = newBytes;
55        }
56        System.arraycopy(buffer, offset, bytes, count, length);
57        count += length;
58    }
59
60    public void write(int b) {
61        if (count == bytes.length) {
62            byte[] newBytes = new byte[count * 2];
63            System.arraycopy(bytes, 0, newBytes, 0, count);
64            bytes = newBytes;
65        }
66        bytes[count++] = (byte) b;
67    }
68
69    public byte[] toByteArray() {
70        if (count == bytes.length) {
71            return bytes;
72        }
73        byte[] result = new byte[count];
74        System.arraycopy(bytes, 0, result, 0, count);
75        return result;
76    }
77
78    public String toString(Charset cs) {
79        return new String(bytes, 0, count, cs);
80    }
81}
82