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.mqtt;
018
019import org.fusesource.mqtt.codec.CONNECT;
020import org.fusesource.mqtt.codec.DISCONNECT;
021import org.fusesource.mqtt.codec.PINGREQ;
022import org.fusesource.mqtt.codec.PUBACK;
023import org.fusesource.mqtt.codec.PUBCOMP;
024import org.fusesource.mqtt.codec.PUBLISH;
025import org.fusesource.mqtt.codec.PUBREC;
026import org.fusesource.mqtt.codec.PUBREL;
027import org.fusesource.mqtt.codec.SUBSCRIBE;
028import org.fusesource.mqtt.codec.UNSUBSCRIBE;
029
030/**
031 * A set of static methods useful for handling MQTT based client connections.
032 */
033public class MQTTProtocolSupport {
034
035    /**
036     * Converts an MQTT formatted Topic name into a suitable ActiveMQ Destination
037     * name string.
038     *
039     * @param name
040     *        the MQTT formatted topic name.
041     *
042     * @return an destination name that fits the ActiveMQ conventions.
043     */
044    public static String convertMQTTToActiveMQ(String name) {
045        char[] chars = name.toCharArray();
046        for (int i = 0; i < chars.length; i++) {
047            switch(chars[i]) {
048                case '#':
049                    chars[i] = '>';
050                    break;
051                case '>':
052                    chars[i] = '#';
053                    break;
054                case '+':
055                    chars[i] = '*';
056                    break;
057                case '*':
058                    chars[i] = '+';
059                    break;
060                case '/':
061                    chars[i] = '.';
062                    break;
063                case '.':
064                    chars[i] = '/';
065                    break;
066            }
067        }
068        String rc = new String(chars);
069        return rc;
070    }
071
072    /**
073     * Converts an ActiveMQ destination name into a correctly formatted
074     * MQTT destination name.
075     *
076     * @param destinationName
077     *        the ActiveMQ destination name to process.
078     *
079     * @return a destination name formatted for MQTT.
080     */
081    public static String convertActiveMQToMQTT(String destinationName) {
082        char[] chars = destinationName.toCharArray();
083        for (int i = 0; i < chars.length; i++) {
084            switch(chars[i]) {
085                case '>':
086                    chars[i] = '#';
087                    break;
088                case '#':
089                    chars[i] = '>';
090                    break;
091                case '*':
092                    chars[i] = '+';
093                    break;
094                case '+':
095                    chars[i] = '*';
096                    break;
097                case '.':
098                    chars[i] = '/';
099                    break;
100                case '/':
101                    chars[i] = '.';
102                    break;
103            }
104        }
105        String rc = new String(chars);
106        return rc;
107    }
108
109    /**
110     * Given an MQTT header byte, determine the command type that the header
111     * represents.
112     *
113     * @param header
114     *        the byte value for the MQTT frame header.
115     *
116     * @return a string value for the given command type.
117     */
118    public static String commandType(byte header) {
119        byte messageType = (byte) ((header & 0xF0) >>> 4);
120        switch (messageType) {
121            case PINGREQ.TYPE:
122                return "PINGREQ";
123            case CONNECT.TYPE:
124                return "CONNECT";
125            case DISCONNECT.TYPE:
126                return "DISCONNECT";
127            case SUBSCRIBE.TYPE:
128                return "SUBSCRIBE";
129            case UNSUBSCRIBE.TYPE:
130                return "UNSUBSCRIBE";
131            case PUBLISH.TYPE:
132                return "PUBLISH";
133            case PUBACK.TYPE:
134                return "PUBACK";
135            case PUBREC.TYPE:
136                return "PUBREC";
137            case PUBREL.TYPE:
138                return "PUBREL";
139            case PUBCOMP.TYPE:
140                return "PUBCOMP";
141            default:
142                return "UNKNOWN";
143        }
144    }
145}