1 /*
2  * $HeadURL: http://svn.apache.org/repos/asf/httpcomponents/httpcore/trunk/module-main/src/main/java/org/apache/http/util/ByteArrayBuffer.java $
3  * $Revision: 496070 $
4  * $Date: 2007-01-14 04:18:34 -0800 (Sun, 14 Jan 2007) $
5  *
6  * ====================================================================
7  * Licensed to the Apache Software Foundation (ASF) under one
8  * or more contributor license agreements.  See the NOTICE file
9  * distributed with this work for additional information
10  * regarding copyright ownership.  The ASF licenses this file
11  * to you under the Apache License, Version 2.0 (the
12  * "License"); you may not use this file except in compliance
13  * with the License.  You may obtain a copy of the License at
14  *
15  *   http://www.apache.org/licenses/LICENSE-2.0
16  *
17  * Unless required by applicable law or agreed to in writing,
18  * software distributed under the License is distributed on an
19  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
20  * KIND, either express or implied.  See the License for the
21  * specific language governing permissions and limitations
22  * under the License.
23  * ====================================================================
24  *
25  * This software consists of voluntary contributions made by many
26  * individuals on behalf of the Apache Software Foundation.  For more
27  * information on the Apache Software Foundation, please see
28  * <http://www.apache.org/>.
29  *
30  */
31 
32 package com.android.usbtuner.util;
33 
34 /**
35  * An expandable byte buffer built on byte array.
36  */
37 public final class ByteArrayBuffer {
38 
39     private byte[] buffer;
40     private int len;
41 
ByteArrayBuffer(int capacity)42     public ByteArrayBuffer(int capacity) {
43         super();
44         if (capacity < 0) {
45             throw new IllegalArgumentException("Buffer capacity may not be negative");
46         }
47         this.buffer = new byte[capacity];
48     }
49 
expand(int newlen)50     private void expand(int newlen) {
51         byte newbuffer[] = new byte[Math.max(this.buffer.length << 1, newlen)];
52         System.arraycopy(this.buffer, 0, newbuffer, 0, this.len);
53         this.buffer = newbuffer;
54     }
55 
append(final byte[] b, int off, int len)56     public void append(final byte[] b, int off, int len) {
57         if (b == null) {
58             return;
59         }
60         if ((off < 0) || (off > b.length) || (len < 0) ||
61                 ((off + len) < 0) || ((off + len) > b.length)) {
62             throw new IndexOutOfBoundsException();
63         }
64         if (len == 0) {
65             return;
66         }
67         int newlen = this.len + len;
68         if (newlen > this.buffer.length) {
69             expand(newlen);
70         }
71         System.arraycopy(b, off, this.buffer, this.len, len);
72         this.len = newlen;
73     }
74 
append(int b)75     public void append(int b) {
76         int newlen = this.len + 1;
77         if (newlen > this.buffer.length) {
78             expand(newlen);
79         }
80         this.buffer[this.len] = (byte) b;
81         this.len = newlen;
82     }
83 
append(final char[] b, int off, int len)84     public void append(final char[] b, int off, int len) {
85         if (b == null) {
86             return;
87         }
88         if ((off < 0) || (off > b.length) || (len < 0) ||
89                 ((off + len) < 0) || ((off + len) > b.length)) {
90             throw new IndexOutOfBoundsException();
91         }
92         if (len == 0) {
93             return;
94         }
95         int oldlen = this.len;
96         int newlen = oldlen + len;
97         if (newlen > this.buffer.length) {
98             expand(newlen);
99         }
100         for (int i1 = off, i2 = oldlen; i2 < newlen; i1++, i2++) {
101             this.buffer[i2] = (byte) b[i1];
102         }
103         this.len = newlen;
104     }
105 
clear()106     public void clear() {
107         this.len = 0;
108     }
109 
toByteArray()110     public byte[] toByteArray() {
111         byte[] b = new byte[this.len];
112         if (this.len > 0) {
113             System.arraycopy(this.buffer, 0, b, 0, this.len);
114         }
115         return b;
116     }
117 
byteAt(int i)118     public int byteAt(int i) {
119         return this.buffer[i];
120     }
121 
capacity()122     public int capacity() {
123         return this.buffer.length;
124     }
125 
length()126     public int length() {
127         return this.len;
128     }
129 
buffer()130     public byte[] buffer() {
131         return this.buffer;
132     }
133 
setLength(int len)134     public void setLength(int len) {
135         if (len < 0 || len > this.buffer.length) {
136             throw new IndexOutOfBoundsException();
137         }
138         this.len = len;
139     }
140 
isEmpty()141     public boolean isEmpty() {
142         return this.len == 0;
143     }
144 
isFull()145     public boolean isFull() {
146         return this.len == this.buffer.length;
147     }
148 
149 }
150