[44] | 1 | package omq.common.broker; |
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| 2 | |
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| 3 | import java.io.IOException; |
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| 4 | import java.util.HashMap; |
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| 5 | import java.util.Map; |
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| 6 | import java.util.Properties; |
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| 7 | |
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| 8 | import omq.Remote; |
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| 9 | import omq.client.listener.ResponseListener; |
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| 10 | import omq.client.proxy.Proxymq; |
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| 11 | import omq.common.event.Event; |
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| 12 | import omq.common.event.EventDispatcher; |
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| 13 | import omq.common.event.EventWrapper; |
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| 14 | import omq.common.util.Environment; |
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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.exception.SerializerException; |
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| 21 | import omq.server.RemoteObject; |
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| 22 | |
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| 23 | import com.rabbitmq.client.Channel; |
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| 24 | import com.rabbitmq.client.Connection; |
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| 25 | import com.rabbitmq.client.QueueingConsumer; |
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| 26 | import com.rabbitmq.client.QueueingConsumer.Delivery; |
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| 27 | import com.rabbitmq.client.ShutdownListener; |
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| 28 | import com.rabbitmq.client.ShutdownSignalException; |
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| 29 | |
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| 30 | public class Broker { |
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| 31 | private static Connection connection; |
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| 32 | private static Channel channel; |
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| 33 | private static boolean clientStarted = false; |
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| 34 | private static boolean connectionClosed = false; |
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| 35 | // TODO ask Pedro if it can be only one object in the map (an object can |
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| 36 | // have multiple threads in the same broker -see environment-) |
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| 37 | private static Map<String, RemoteObject> remoteObjs; |
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| 38 | |
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| 39 | /** |
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| 40 | * Initializes a new Broker with the environment called by reference |
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| 41 | * |
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| 42 | * @param env |
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| 43 | * @throws Exception |
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| 44 | */ |
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| 45 | public static synchronized void initBroker(Properties env) throws Exception { |
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| 46 | if (Environment.isVoid()) { |
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| 47 | remoteObjs = new HashMap<String, RemoteObject>(); |
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| 48 | Environment.setEnvironment(env); |
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| 49 | connection = OmqConnectionFactory.getNewConnection(env); |
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| 50 | channel = connection.createChannel(); |
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| 51 | addFaultTolerance(); |
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| 52 | try { |
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| 53 | tryConnection(env); |
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| 54 | } catch (Exception e) { |
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| 55 | channel.close(); |
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| 56 | connection.close(); |
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| 57 | throw new InitBrokerException("The connection didn't work"); |
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| 58 | } |
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| 59 | } else { |
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| 60 | throw new InitBrokerException("Broker already started"); |
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| 61 | } |
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| 62 | } |
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| 63 | |
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| 64 | public static void stopBroker() throws Exception { |
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| 65 | // Stop the client |
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| 66 | if (clientStarted) { |
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| 67 | ResponseListener.stopResponseListner(); |
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| 68 | EventDispatcher.stopEventDispatcher(); |
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| 69 | } |
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| 70 | // Stop all the remote objects working |
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| 71 | for (String reference : remoteObjs.keySet()) { |
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| 72 | unbind(reference); |
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| 73 | } |
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| 74 | // Close the connection once all the listeners are died |
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| 75 | closeConnection(); |
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| 76 | } |
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| 77 | |
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| 78 | /** |
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| 79 | * @return Broker's connection |
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| 80 | * @throws Exception |
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| 81 | */ |
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| 82 | public static Connection getConnection() throws Exception { |
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| 83 | return connection; |
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| 84 | } |
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| 85 | |
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| 86 | public static void closeConnection() throws IOException { |
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| 87 | connectionClosed = true; |
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| 88 | connection.close(); |
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| 89 | } |
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| 90 | |
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| 91 | /** |
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| 92 | * |
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| 93 | * @return Broker's channel |
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| 94 | * @throws Exception |
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| 95 | */ |
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| 96 | public static Channel getChannel() throws Exception { |
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| 97 | return channel; |
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| 98 | } |
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| 99 | |
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| 100 | /** |
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| 101 | * Creates a new channel using the Broker's connection |
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| 102 | * |
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| 103 | * @return newChannel |
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| 104 | * @throws IOException |
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| 105 | */ |
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| 106 | public static Channel getNewChannel() throws IOException { |
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| 107 | return connection.createChannel(); |
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| 108 | } |
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| 109 | |
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| 110 | @SuppressWarnings("unchecked") |
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| 111 | public static <T extends Remote> T lookup(String reference, Class<T> contract) throws RemoteException { |
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| 112 | try { |
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| 113 | Properties environment = Environment.getEnvironment(); |
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| 114 | |
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| 115 | if (!clientStarted) { |
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| 116 | initClient(environment); |
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| 117 | clientStarted = true; |
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| 118 | } |
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| 119 | |
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| 120 | if (!Proxymq.containsProxy(reference)) { |
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| 121 | Proxymq proxy = new Proxymq(reference, contract, environment); |
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| 122 | Class<?>[] array = { contract }; |
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| 123 | return (T) Proxymq.newProxyInstance(contract.getClassLoader(), array, proxy); |
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| 124 | } |
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| 125 | return (T) Proxymq.getInstance(reference); |
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| 126 | |
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| 127 | } catch (Exception e) { |
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| 128 | throw new RemoteException(e); |
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| 129 | } |
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| 130 | } |
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| 131 | |
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| 132 | public static void bind(String reference, RemoteObject remote) throws RemoteException { |
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| 133 | try { |
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| 134 | Properties environment = Environment.getEnvironment(); |
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| 135 | remote.startRemoteObject(reference, environment); |
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| 136 | remoteObjs.put(reference, remote); |
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| 137 | } catch (Exception e) { |
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| 138 | throw new RemoteException(e); |
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| 139 | } |
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| 140 | } |
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| 141 | |
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| 142 | public static void unbind(String reference) throws RemoteException, IOException { |
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| 143 | if (remoteObjs.containsKey(reference)) { |
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| 144 | RemoteObject remote = remoteObjs.get(reference); |
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| 145 | remote.kill(); |
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| 146 | } else { |
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| 147 | throw new RemoteException("The object referenced by 'reference' does not exist in the Broker"); |
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| 148 | } |
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| 149 | |
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| 150 | } |
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| 151 | |
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| 152 | public void rebind(String name, Remote obj) throws RemoteException { |
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| 153 | |
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| 154 | } |
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| 155 | |
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| 156 | /** |
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| 157 | * This method ensures the client will have only one ResponseListener and |
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| 158 | * only one EventDispatcher. Both with the same environment. |
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| 159 | * |
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| 160 | * @param environment |
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| 161 | * @throws Exception |
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| 162 | */ |
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| 163 | private static synchronized void initClient(Properties environment) throws Exception { |
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| 164 | if (ResponseListener.isVoid()) { |
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| 165 | ResponseListener.init(environment); |
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| 166 | } |
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| 167 | if (EventDispatcher.isVoid()) { |
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| 168 | EventDispatcher.init(environment); |
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| 169 | } |
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| 170 | } |
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| 171 | |
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| 172 | /** |
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| 173 | * This method sends an event with its information |
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| 174 | * |
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| 175 | * @param event |
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| 176 | * @throws IOException |
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| 177 | * @throws SerializerException |
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| 178 | */ |
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| 179 | public static void trigger(Event event) throws IOException, SerializerException { |
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| 180 | String UID = event.getTopic(); |
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| 181 | EventWrapper wrapper = new EventWrapper(event); |
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| 182 | System.out.println("EventTrigger fanout exchange: " + UID + " Event topic: " + UID + " Event corrID: " + event.getCorrId()); |
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| 183 | channel.exchangeDeclare(UID, "fanout"); |
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| 184 | |
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| 185 | byte[] bytesResponse = Serializer.serialize(wrapper); |
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| 186 | channel.basicPublish(UID, "", null, bytesResponse); |
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| 187 | |
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| 188 | // Log.saveLog("Server-Serialize", bytesResponse); |
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| 189 | } |
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| 190 | |
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| 191 | /** |
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| 192 | * This function is used to send a ping message to see if the connection |
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| 193 | * works |
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| 194 | * |
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| 195 | * @param env |
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| 196 | * @throws Exception |
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| 197 | */ |
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| 198 | public static void tryConnection(Properties env) throws Exception { |
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| 199 | Channel channel = connection.createChannel(); |
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| 200 | String message = "ping"; |
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| 201 | |
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| 202 | String exchange = env.getProperty(ParameterQueue.USER_NAME) + "ping"; |
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| 203 | String queueName = exchange; |
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| 204 | String routingKey = "routingKey"; |
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| 205 | |
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| 206 | channel.exchangeDeclare(exchange, "direct"); |
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| 207 | channel.queueDeclare(queueName, false, false, false, null); |
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| 208 | channel.queueBind(queueName, exchange, routingKey); |
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| 209 | |
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| 210 | channel.basicPublish(exchange, routingKey, null, message.getBytes()); |
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| 211 | |
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| 212 | QueueingConsumer consumer = new QueueingConsumer(channel); |
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| 213 | |
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| 214 | channel.basicConsume(queueName, true, consumer); |
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| 215 | Delivery delivery = consumer.nextDelivery(1000); |
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| 216 | |
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| 217 | channel.exchangeDelete(exchange); |
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| 218 | channel.queueDelete(queueName); |
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| 219 | |
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| 220 | channel.close(); |
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| 221 | |
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| 222 | if (!message.equalsIgnoreCase(new String(delivery.getBody()))) { |
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| 223 | throw new IOException("Ping initialitzation has failed"); |
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| 224 | } |
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| 225 | } |
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| 226 | |
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| 227 | /** |
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| 228 | * This method adds a ShutdownListener to the Broker's connection. When this |
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| 229 | * connection falls, a new connection will be created and this will also |
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| 230 | * have the listener. |
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| 231 | */ |
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| 232 | private static void addFaultTolerance() { |
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| 233 | connection.addShutdownListener(new ShutdownListener() { |
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| 234 | @Override |
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| 235 | public void shutdownCompleted(ShutdownSignalException cause) { |
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| 236 | if (!connectionClosed) |
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| 237 | if (cause.isHardError()) { |
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| 238 | if (connection.isOpen()) { |
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| 239 | try { |
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| 240 | connection.close(); |
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| 241 | } catch (IOException e) { |
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| 242 | e.printStackTrace(); |
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| 243 | } |
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| 244 | } |
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| 245 | try { |
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| 246 | Properties env = Environment.getEnvironment(); |
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| 247 | connection = OmqConnectionFactory.getNewWorkingConnection(env); |
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| 248 | channel = connection.createChannel(); |
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| 249 | addFaultTolerance(); |
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| 250 | } catch (Exception e) { |
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| 251 | e.printStackTrace(); |
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| 252 | } |
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| 253 | } else { |
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| 254 | Channel channel = (Channel) cause.getReference(); |
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| 255 | if (channel.isOpen()) { |
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| 256 | try { |
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| 257 | channel.close(); |
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| 258 | } catch (IOException e) { |
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| 259 | e.printStackTrace(); |
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| 260 | } |
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| 261 | } |
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| 262 | } |
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| 263 | } |
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| 264 | }); |
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| 265 | } |
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| 266 | |
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| 267 | } |
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