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 */
017package org.apache.activemq.transport.amqp;
018
019import org.fusesource.hawtbuf.Buffer;
020
021/**
022 * Represents the AMQP protocol handshake packet that is sent during the
023 * initial exchange with a remote peer.
024 */
025public class AmqpHeader {
026
027    static final Buffer PREFIX = new Buffer(new byte[] { 'A', 'M', 'Q', 'P' });
028
029    private Buffer buffer;
030
031    public AmqpHeader() {
032        this(new Buffer(new byte[] { 'A', 'M', 'Q', 'P', 0, 1, 0, 0 }));
033    }
034
035    public AmqpHeader(Buffer buffer) {
036        this(buffer, true);
037    }
038
039    public AmqpHeader(Buffer buffer, boolean validate) {
040        setBuffer(buffer, validate);
041    }
042
043    public int getProtocolId() {
044        return buffer.get(4) & 0xFF;
045    }
046
047    public void setProtocolId(int value) {
048        buffer.data[buffer.offset + 4] = (byte) value;
049    }
050
051    public int getMajor() {
052        return buffer.get(5) & 0xFF;
053    }
054
055    public void setMajor(int value) {
056        buffer.data[buffer.offset + 5] = (byte) value;
057    }
058
059    public int getMinor() {
060        return buffer.get(6) & 0xFF;
061    }
062
063    public void setMinor(int value) {
064        buffer.data[buffer.offset + 6] = (byte) value;
065    }
066
067    public int getRevision() {
068        return buffer.get(7) & 0xFF;
069    }
070
071    public void setRevision(int value) {
072        buffer.data[buffer.offset + 7] = (byte) value;
073    }
074
075    public Buffer getBuffer() {
076        return buffer;
077    }
078
079    public void setBuffer(Buffer value) {
080        setBuffer(value, true);
081    }
082
083    public void setBuffer(Buffer value, boolean validate) {
084        if (validate && !value.startsWith(PREFIX) || value.length() != 8) {
085            throw new IllegalArgumentException("Not an AMQP header buffer");
086        }
087        buffer = value.buffer();
088    }
089
090    public boolean hasValidPrefix() {
091        return buffer.startsWith(PREFIX);
092    }
093
094    @Override
095    public String toString() {
096        StringBuilder builder = new StringBuilder();
097        for (int i = 0; i < buffer.length(); ++i) {
098            char value = (char) buffer.get(i);
099            if (Character.isLetter(value)) {
100                builder.append(value);
101            } else {
102                builder.append(",");
103                builder.append((int) value);
104            }
105        }
106        return builder.toString();
107    }
108}