001/**
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package org.apache.activemq.util;
019
020public class ByteSequence {
021
022    public byte[] data;
023    public int offset;
024    public int length;
025
026    public ByteSequence() {
027    }
028
029    public ByteSequence(byte data[]) {
030        this.data = data;
031        this.offset = 0;
032        this.length = data.length;
033    }
034
035    public ByteSequence(byte data[], int offset, int length) {
036        this.data = data;
037        this.offset = offset;
038        this.length = length;
039    }
040
041    public byte[] getData() {
042        return data;
043    }
044
045    public int getLength() {
046        return length;
047    }
048
049    public int getOffset() {
050        return offset;
051    }
052
053    public void setData(byte[] data) {
054        this.data = data;
055    }
056
057    public void setLength(int length) {
058        this.length = length;
059    }
060
061    public void setOffset(int offset) {
062        this.offset = offset;
063    }
064
065    public void compact() {
066        if (length != data.length) {
067            byte t[] = new byte[length];
068            System.arraycopy(data, offset, t, 0, length);
069            data = t;
070            offset = 0;
071        }
072    }
073
074    public int indexOf(ByteSequence needle, int pos) {
075        int max = length - needle.length;
076        for (int i = pos; i < max; i++) {
077            if (matches(needle, i)) {
078                return i;
079            }
080        }
081        return -1;
082    }
083
084    private boolean matches(ByteSequence needle, int pos) {
085        for (int i = 0; i < needle.length; i++) {
086            if( data[offset + pos+ i] != needle.data[needle.offset + i] ) {
087                return false;
088            }
089        }
090        return true;
091    }
092
093    private byte getByte(int i) {
094        return data[offset+i];
095    }
096
097    final public int indexOf(byte value, int pos) {
098        for (int i = pos; i < length; i++) {
099            if (data[offset + i] == value) {
100                return i;
101            }
102        }
103        return -1;
104    }
105}