[44] | 1 | package omq.common.broker; |
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| 2 | |
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| 3 | import java.io.IOException; |
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[70] | 4 | import java.lang.reflect.Proxy; |
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[49] | 5 | import java.net.URL; |
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[44] | 6 | import java.util.HashMap; |
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[59] | 7 | import java.util.Hashtable; |
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[44] | 8 | import java.util.Map; |
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| 9 | import java.util.Properties; |
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| 10 | |
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| 11 | import omq.Remote; |
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| 12 | import omq.client.listener.ResponseListener; |
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[70] | 13 | import omq.client.proxy.MultiProxymq; |
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[44] | 14 | import omq.client.proxy.Proxymq; |
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| 15 | import omq.common.util.OmqConnectionFactory; |
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| 16 | import omq.common.util.ParameterQueue; |
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| 17 | import omq.common.util.Serializer; |
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| 18 | import omq.exception.InitBrokerException; |
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| 19 | import omq.exception.RemoteException; |
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| 20 | import omq.server.RemoteObject; |
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| 21 | |
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[49] | 22 | import org.apache.log4j.Logger; |
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| 23 | import org.apache.log4j.xml.DOMConfigurator; |
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| 24 | |
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[44] | 25 | import com.rabbitmq.client.Channel; |
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| 26 | import com.rabbitmq.client.Connection; |
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| 27 | import com.rabbitmq.client.QueueingConsumer; |
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| 28 | import com.rabbitmq.client.QueueingConsumer.Delivery; |
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| 29 | import com.rabbitmq.client.ShutdownListener; |
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| 30 | import com.rabbitmq.client.ShutdownSignalException; |
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| 31 | |
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| 32 | public class Broker { |
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[49] | 33 | |
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| 34 | private static final Logger logger = Logger.getLogger(Broker.class.getName()); |
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| 35 | |
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[53] | 36 | private Connection connection; |
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| 37 | private Channel channel; |
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| 38 | private ResponseListener responseListener; |
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| 39 | private Serializer serializer; |
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| 40 | private boolean clientStarted = false; |
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| 41 | private boolean connectionClosed = false; |
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| 42 | private Properties environment = null; |
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| 43 | private Map<String, RemoteObject> remoteObjs; |
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[59] | 44 | private Map<String, Object> proxies = new Hashtable<String, Object>(); |
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[70] | 45 | private Map<String, Object> multiProxies = new Hashtable<String, Object>(); |
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[44] | 46 | |
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[53] | 47 | public Broker(Properties env) throws Exception { |
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| 48 | // Load log4j configuration |
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| 49 | URL log4jResource = Broker.class.getResource("/log4j.xml"); |
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| 50 | DOMConfigurator.configure(log4jResource); |
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[49] | 51 | |
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[53] | 52 | remoteObjs = new HashMap<String, RemoteObject>(); |
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| 53 | serializer = new Serializer(env); |
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| 54 | environment = env; |
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| 55 | connection = OmqConnectionFactory.getNewConnection(env); |
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| 56 | channel = connection.createChannel(); |
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| 57 | addFaultTolerance(); |
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| 58 | try { |
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| 59 | tryConnection(env); |
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| 60 | } catch (Exception e) { |
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| 61 | channel.close(); |
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| 62 | connection.close(); |
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| 63 | throw new InitBrokerException("The connection didn't work"); |
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[44] | 64 | } |
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| 65 | } |
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| 66 | |
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[53] | 67 | public void stopBroker() throws Exception { |
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[49] | 68 | logger.warn("Stopping broker"); |
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[44] | 69 | // Stop the client |
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| 70 | if (clientStarted) { |
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[53] | 71 | responseListener.kill(); |
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[70] | 72 | // TODO proxies = null; ?? |
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[44] | 73 | } |
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| 74 | // Stop all the remote objects working |
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| 75 | for (String reference : remoteObjs.keySet()) { |
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| 76 | unbind(reference); |
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| 77 | } |
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[47] | 78 | |
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[44] | 79 | // Close the connection once all the listeners are died |
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| 80 | closeConnection(); |
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[47] | 81 | |
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| 82 | clientStarted = false; |
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| 83 | connectionClosed = false; |
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| 84 | environment = null; |
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| 85 | remoteObjs = null; |
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[53] | 86 | // Serializer.removeSerializers(); |
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[44] | 87 | } |
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| 88 | |
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| 89 | /** |
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| 90 | * @return Broker's connection |
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| 91 | * @throws Exception |
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| 92 | */ |
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[53] | 93 | public Connection getConnection() throws Exception { |
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[44] | 94 | return connection; |
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| 95 | } |
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| 96 | |
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[53] | 97 | public void closeConnection() throws IOException { |
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[49] | 98 | logger.warn("Clossing connection"); |
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[44] | 99 | connectionClosed = true; |
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| 100 | connection.close(); |
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[47] | 101 | connectionClosed = false; |
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[44] | 102 | } |
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| 103 | |
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| 104 | /** |
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| 105 | * |
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| 106 | * @return Broker's channel |
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| 107 | * @throws Exception |
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| 108 | */ |
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[53] | 109 | public Channel getChannel() throws Exception { |
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[44] | 110 | return channel; |
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| 111 | } |
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| 112 | |
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| 113 | /** |
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| 114 | * Creates a new channel using the Broker's connection |
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| 115 | * |
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| 116 | * @return newChannel |
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| 117 | * @throws IOException |
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| 118 | */ |
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[53] | 119 | public Channel getNewChannel() throws IOException { |
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[44] | 120 | return connection.createChannel(); |
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| 121 | } |
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| 122 | |
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| 123 | @SuppressWarnings("unchecked") |
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[59] | 124 | public synchronized <T extends Remote> T lookup(String reference, Class<T> contract) throws RemoteException { |
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[44] | 125 | try { |
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| 126 | |
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| 127 | if (!clientStarted) { |
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| 128 | initClient(environment); |
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| 129 | clientStarted = true; |
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| 130 | } |
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| 131 | |
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[59] | 132 | if (!proxies.containsKey(reference)) { |
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[53] | 133 | Proxymq proxy = new Proxymq(reference, contract, this); |
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[44] | 134 | Class<?>[] array = { contract }; |
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[70] | 135 | Object newProxy = Proxy.newProxyInstance(contract.getClassLoader(), array, proxy); |
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[59] | 136 | proxies.put(reference, newProxy); |
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| 137 | return (T) newProxy; |
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[44] | 138 | } |
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[59] | 139 | return (T) proxies.get(reference); |
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[44] | 140 | |
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| 141 | } catch (Exception e) { |
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| 142 | throw new RemoteException(e); |
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| 143 | } |
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| 144 | } |
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| 145 | |
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[70] | 146 | @SuppressWarnings("unchecked") |
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| 147 | public synchronized <T extends Remote> T lookupMulti(String reference, Class<T> contract) throws RemoteException { |
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| 148 | try { |
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| 149 | if (!multiProxies.containsKey(reference)) { |
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| 150 | MultiProxymq proxy = new MultiProxymq(reference, contract, this); |
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| 151 | Class<?>[] array = { contract }; |
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| 152 | Object newProxy = Proxy.newProxyInstance(contract.getClassLoader(), array, proxy); |
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| 153 | multiProxies.put(reference, newProxy); |
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| 154 | return (T) newProxy; |
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| 155 | } |
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| 156 | return (T) multiProxies.get(reference); |
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| 157 | |
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| 158 | } catch (Exception e) { |
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| 159 | throw new RemoteException(e); |
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| 160 | } |
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| 161 | } |
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| 162 | |
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[53] | 163 | public void bind(String reference, RemoteObject remote) throws RemoteException { |
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[44] | 164 | try { |
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[53] | 165 | remote.startRemoteObject(reference, this); |
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[44] | 166 | remoteObjs.put(reference, remote); |
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| 167 | } catch (Exception e) { |
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| 168 | throw new RemoteException(e); |
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| 169 | } |
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| 170 | } |
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[70] | 171 | |
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[66] | 172 | public void startTriggerEvent(String reference, RemoteObject remote) throws RemoteException { |
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| 173 | try { |
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| 174 | remote.startTriggerEvent(reference, this); |
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| 175 | remoteObjs.put(reference, remote); |
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| 176 | } catch (Exception e) { |
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| 177 | throw new RemoteException(e); |
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| 178 | } |
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| 179 | } |
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[44] | 180 | |
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[53] | 181 | public void unbind(String reference) throws RemoteException, IOException { |
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[44] | 182 | if (remoteObjs.containsKey(reference)) { |
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| 183 | RemoteObject remote = remoteObjs.get(reference); |
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| 184 | remote.kill(); |
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| 185 | } else { |
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| 186 | throw new RemoteException("The object referenced by 'reference' does not exist in the Broker"); |
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| 187 | } |
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| 188 | |
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| 189 | } |
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| 190 | |
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| 191 | public void rebind(String name, Remote obj) throws RemoteException { |
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| 192 | |
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| 193 | } |
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| 194 | |
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| 195 | /** |
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| 196 | * This method ensures the client will have only one ResponseListener and |
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| 197 | * only one EventDispatcher. Both with the same environment. |
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| 198 | * |
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| 199 | * @param environment |
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| 200 | * @throws Exception |
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| 201 | */ |
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[53] | 202 | private synchronized void initClient(Properties environment) throws Exception { |
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| 203 | if (responseListener == null) { |
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| 204 | responseListener = new ResponseListener(this); |
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[54] | 205 | responseListener.start(); |
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[44] | 206 | } |
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| 207 | } |
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| 208 | |
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| 209 | /** |
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| 210 | * This function is used to send a ping message to see if the connection |
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| 211 | * works |
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| 212 | * |
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| 213 | * @param env |
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| 214 | * @throws Exception |
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| 215 | */ |
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[53] | 216 | public void tryConnection(Properties env) throws Exception { |
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[44] | 217 | Channel channel = connection.createChannel(); |
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| 218 | String message = "ping"; |
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| 219 | |
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| 220 | String exchange = env.getProperty(ParameterQueue.USER_NAME) + "ping"; |
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| 221 | String queueName = exchange; |
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| 222 | String routingKey = "routingKey"; |
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| 223 | |
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| 224 | channel.exchangeDeclare(exchange, "direct"); |
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| 225 | channel.queueDeclare(queueName, false, false, false, null); |
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| 226 | channel.queueBind(queueName, exchange, routingKey); |
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| 227 | |
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| 228 | channel.basicPublish(exchange, routingKey, null, message.getBytes()); |
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| 229 | |
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| 230 | QueueingConsumer consumer = new QueueingConsumer(channel); |
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| 231 | |
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| 232 | channel.basicConsume(queueName, true, consumer); |
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| 233 | Delivery delivery = consumer.nextDelivery(1000); |
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| 234 | |
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| 235 | channel.exchangeDelete(exchange); |
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| 236 | channel.queueDelete(queueName); |
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| 237 | |
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| 238 | channel.close(); |
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| 239 | |
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| 240 | if (!message.equalsIgnoreCase(new String(delivery.getBody()))) { |
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| 241 | throw new IOException("Ping initialitzation has failed"); |
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| 242 | } |
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| 243 | } |
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| 244 | |
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| 245 | /** |
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| 246 | * This method adds a ShutdownListener to the Broker's connection. When this |
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| 247 | * connection falls, a new connection will be created and this will also |
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| 248 | * have the listener. |
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| 249 | */ |
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[53] | 250 | private void addFaultTolerance() { |
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[44] | 251 | connection.addShutdownListener(new ShutdownListener() { |
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| 252 | @Override |
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| 253 | public void shutdownCompleted(ShutdownSignalException cause) { |
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[49] | 254 | logger.warn("Shutdown message received. Cause: " + cause.getMessage()); |
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[44] | 255 | if (!connectionClosed) |
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| 256 | if (cause.isHardError()) { |
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| 257 | if (connection.isOpen()) { |
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| 258 | try { |
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| 259 | connection.close(); |
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| 260 | } catch (IOException e) { |
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| 261 | e.printStackTrace(); |
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| 262 | } |
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| 263 | } |
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| 264 | try { |
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[47] | 265 | connection = OmqConnectionFactory.getNewWorkingConnection(environment); |
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[44] | 266 | channel = connection.createChannel(); |
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| 267 | addFaultTolerance(); |
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| 268 | } catch (Exception e) { |
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| 269 | e.printStackTrace(); |
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| 270 | } |
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| 271 | } else { |
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| 272 | Channel channel = (Channel) cause.getReference(); |
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| 273 | if (channel.isOpen()) { |
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| 274 | try { |
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| 275 | channel.close(); |
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| 276 | } catch (IOException e) { |
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| 277 | e.printStackTrace(); |
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| 278 | } |
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| 279 | } |
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| 280 | } |
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| 281 | } |
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| 282 | }); |
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| 283 | } |
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| 284 | |
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[53] | 285 | public Properties getEnvironment() { |
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[47] | 286 | return environment; |
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| 287 | } |
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| 288 | |
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[53] | 289 | public ResponseListener getResponseListener() { |
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| 290 | return responseListener; |
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| 291 | } |
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| 292 | |
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| 293 | public Serializer getSerializer() { |
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| 294 | return serializer; |
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| 295 | } |
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[44] | 296 | } |
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