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 java.io.DataOutputStream; 020import java.io.EOFException; 021import java.io.IOException; 022import java.net.Socket; 023import java.net.URI; 024import java.net.UnknownHostException; 025import java.nio.ByteBuffer; 026import java.nio.channels.SelectionKey; 027import java.nio.channels.SocketChannel; 028 029import javax.net.SocketFactory; 030 031import org.apache.activemq.transport.nio.NIOOutputStream; 032import org.apache.activemq.transport.nio.SelectorManager; 033import org.apache.activemq.transport.nio.SelectorSelection; 034import org.apache.activemq.transport.tcp.TcpTransport; 035import org.apache.activemq.util.IOExceptionSupport; 036import org.apache.activemq.util.ServiceStopper; 037import org.apache.activemq.wireformat.WireFormat; 038import org.fusesource.hawtbuf.DataByteArrayInputStream; 039 040/** 041 * An implementation of the {@link org.apache.activemq.transport.Transport} interface for using MQTT over NIO 042 */ 043public class MQTTNIOTransport extends TcpTransport { 044 045 private SocketChannel channel; 046 private SelectorSelection selection; 047 048 private ByteBuffer inputBuffer; 049 MQTTCodec codec; 050 051 public MQTTNIOTransport(WireFormat wireFormat, SocketFactory socketFactory, URI remoteLocation, URI localLocation) throws UnknownHostException, IOException { 052 super(wireFormat, socketFactory, remoteLocation, localLocation); 053 } 054 055 public MQTTNIOTransport(WireFormat wireFormat, Socket socket) throws IOException { 056 super(wireFormat, socket); 057 } 058 059 @Override 060 protected void initializeStreams() throws IOException { 061 channel = socket.getChannel(); 062 channel.configureBlocking(false); 063 // listen for events telling us when the socket is readable. 064 selection = SelectorManager.getInstance().register(channel, new SelectorManager.Listener() { 065 @Override 066 public void onSelect(SelectorSelection selection) { 067 if (!isStopped()) { 068 serviceRead(); 069 } 070 } 071 072 @Override 073 public void onError(SelectorSelection selection, Throwable error) { 074 if (error instanceof IOException) { 075 onException((IOException) error); 076 } else { 077 onException(IOExceptionSupport.create(error)); 078 } 079 } 080 }); 081 082 inputBuffer = ByteBuffer.allocate(8 * 1024); 083 NIOOutputStream outPutStream = new NIOOutputStream(channel, 8 * 1024); 084 dataOut = new DataOutputStream(outPutStream); 085 buffOut = outPutStream; 086 codec = new MQTTCodec(this, (MQTTWireFormat) getWireFormat()); 087 } 088 089 private void serviceRead() { 090 try { 091 092 while (isStarted()) { 093 // read channel 094 int readSize = channel.read(inputBuffer); 095 // channel is closed, cleanup 096 if (readSize == -1) { 097 onException(new EOFException()); 098 selection.close(); 099 break; 100 } 101 // nothing more to read, break 102 if (readSize == 0) { 103 break; 104 } 105 106 inputBuffer.flip(); 107 DataByteArrayInputStream dis = new DataByteArrayInputStream(inputBuffer.array()); 108 codec.parse(dis, readSize); 109 110 receiveCounter += readSize; 111 112 // clear the buffer 113 inputBuffer.clear(); 114 } 115 } catch (IOException e) { 116 onException(e); 117 } catch (Throwable e) { 118 onException(IOExceptionSupport.create(e)); 119 } 120 } 121 122 @Override 123 protected void doStart() throws Exception { 124 connect(); 125 selection.setInterestOps(SelectionKey.OP_READ); 126 selection.enable(); 127 } 128 129 @Override 130 protected void doStop(ServiceStopper stopper) throws Exception { 131 try { 132 if (selection != null) { 133 selection.close(); 134 } 135 } finally { 136 super.doStop(stopper); 137 } 138 } 139}