Home | History | Annotate | Download | only in util 
      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  * For the license checker
     31  * Licensed under the Apache License, Version 2.0
     32  *
     33  */
     34 
     35 package com.android.tv.tuner.util;
     36 
     37 /** An expandable byte buffer built on byte array. */
     38 public final class ByteArrayBuffer {
     39 
     40     private byte[] buffer;
     41     private int len;
     42 
     43     public ByteArrayBuffer(int capacity) {
     44         super();
     45         if (capacity < 0) {
     46             throw new IllegalArgumentException("Buffer capacity may not be negative");
     47         }
     48         this.buffer = new byte[capacity];
     49     }
     50 
     51     private void expand(int newlen) {
     52         byte newbuffer[] = new byte[Math.max(this.buffer.length << 1, newlen)];
     53         System.arraycopy(this.buffer, 0, newbuffer, 0, this.len);
     54         this.buffer = newbuffer;
     55     }
     56 
     57     public void append(final byte[] b, int off, int len) {
     58         if (b == null) {
     59             return;
     60         }
     61         if ((off < 0)
     62                 || (off > b.length)
     63                 || (len < 0)
     64                 || ((off + len) < 0)
     65                 || ((off + len) > b.length)) {
     66             throw new IndexOutOfBoundsException();
     67         }
     68         if (len == 0) {
     69             return;
     70         }
     71         int newlen = this.len + len;
     72         if (newlen > this.buffer.length) {
     73             expand(newlen);
     74         }
     75         System.arraycopy(b, off, this.buffer, this.len, len);
     76         this.len = newlen;
     77     }
     78 
     79     public void append(int b) {
     80         int newlen = this.len + 1;
     81         if (newlen > this.buffer.length) {
     82             expand(newlen);
     83         }
     84         this.buffer[this.len] = (byte) b;
     85         this.len = newlen;
     86     }
     87 
     88     public void append(final char[] b, int off, int len) {
     89         if (b == null) {
     90             return;
     91         }
     92         if ((off < 0)
     93                 || (off > b.length)
     94                 || (len < 0)
     95                 || ((off + len) < 0)
     96                 || ((off + len) > b.length)) {
     97             throw new IndexOutOfBoundsException();
     98         }
     99         if (len == 0) {
    100             return;
    101         }
    102         int oldlen = this.len;
    103         int newlen = oldlen + len;
    104         if (newlen > this.buffer.length) {
    105             expand(newlen);
    106         }
    107         for (int i1 = off, i2 = oldlen; i2 < newlen; i1++, i2++) {
    108             this.buffer[i2] = (byte) b[i1];
    109         }
    110         this.len = newlen;
    111     }
    112 
    113     public void clear() {
    114         this.len = 0;
    115     }
    116 
    117     public byte[] toByteArray() {
    118         byte[] b = new byte[this.len];
    119         if (this.len > 0) {
    120             System.arraycopy(this.buffer, 0, b, 0, this.len);
    121         }
    122         return b;
    123     }
    124 
    125     public int byteAt(int i) {
    126         return this.buffer[i];
    127     }
    128 
    129     public int capacity() {
    130         return this.buffer.length;
    131     }
    132 
    133     public int length() {
    134         return this.len;
    135     }
    136 
    137     public byte[] buffer() {
    138         return this.buffer;
    139     }
    140 
    141     public void setLength(int len) {
    142         if (len < 0 || len > this.buffer.length) {
    143             throw new IndexOutOfBoundsException();
    144         }
    145         this.len = len;
    146     }
    147 
    148     public boolean isEmpty() {
    149         return this.len == 0;
    150     }
    151 
    152     public boolean isFull() {
    153         return this.len == this.buffer.length;
    154     }
    155 }
    156