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 public MQTTNIOTransport(WireFormat wireFormat, Socket socket, InitBuffer initBuffer) throws IOException { 060 super(wireFormat, socket, initBuffer); 061 } 062 063 @Override 064 protected void initializeStreams() throws IOException { 065 channel = socket.getChannel(); 066 channel.configureBlocking(false); 067 // listen for events telling us when the socket is readable. 068 selection = SelectorManager.getInstance().register(channel, new SelectorManager.Listener() { 069 @Override 070 public void onSelect(SelectorSelection selection) { 071 if (!isStopped()) { 072 serviceRead(); 073 } 074 } 075 076 @Override 077 public void onError(SelectorSelection selection, Throwable error) { 078 if (error instanceof IOException) { 079 onException((IOException) error); 080 } else { 081 onException(IOExceptionSupport.create(error)); 082 } 083 } 084 }); 085 086 inputBuffer = ByteBuffer.allocate(8 * 1024); 087 NIOOutputStream outPutStream = new NIOOutputStream(channel, 8 * 1024); 088 dataOut = new DataOutputStream(outPutStream); 089 buffOut = outPutStream; 090 codec = new MQTTCodec(this, (MQTTWireFormat) getWireFormat()); 091 092 try { 093 if (initBuffer != null) { 094 processBuffer(initBuffer.buffer, initBuffer.readSize); 095 } 096 } catch (IOException e) { 097 onException(e); 098 } catch (Throwable e) { 099 onException(IOExceptionSupport.create(e)); 100 } 101 } 102 103 private void serviceRead() { 104 try { 105 106 while (isStarted()) { 107 // read channel 108 int readSize = channel.read(inputBuffer); 109 // channel is closed, cleanup 110 if (readSize == -1) { 111 onException(new EOFException()); 112 selection.close(); 113 break; 114 } 115 // nothing more to read, break 116 if (readSize == 0) { 117 break; 118 } 119 120 processBuffer(inputBuffer, readSize); 121 } 122 } catch (IOException e) { 123 onException(e); 124 } catch (Throwable e) { 125 onException(IOExceptionSupport.create(e)); 126 } 127 } 128 129 protected void processBuffer(ByteBuffer buffer, int readSize) throws Exception { 130 buffer.flip(); 131 DataByteArrayInputStream dis = new DataByteArrayInputStream(buffer.array()); 132 codec.parse(dis, readSize); 133 134 receiveCounter += readSize; 135 136 // clear the buffer 137 buffer.clear(); 138 } 139 140 @Override 141 protected void doStart() throws Exception { 142 connect(); 143 selection.setInterestOps(SelectionKey.OP_READ); 144 selection.enable(); 145 } 146 147 @Override 148 protected void doStop(ServiceStopper stopper) throws Exception { 149 try { 150 if (selection != null) { 151 selection.close(); 152 } 153 } finally { 154 super.doStop(stopper); 155 } 156 } 157}