io.nats.client.ConnectionFactory Java Examples

@Inject
public NATSEventQueueProvider(Configuration config) {
    logger.info("NATS Event Queue Provider init");
    
    // Init NATS API. Handle "io_nats" and "io.nats" ways to specify parameters
    Properties props = new Properties();
    Properties temp = new Properties();
    temp.putAll(System.getenv());
    temp.putAll(System.getProperties());
    temp.forEach((key1, value) -> {
        String key = key1.toString();
        String val = value.toString();
        
        if (key.startsWith("io_nats")) {
            key = key.replace("_", ".");
        }
        props.put(key, config.getProperty(key, val));
    });
    
    // Init NATS API
    factory = new ConnectionFactory(props);
    logger.info("NATS Event Queue Provider initialized...");
}
 

private void setup() throws Exception {
    connectionFactory = new ConnectionFactory(properties);
    EventHandlers eh = new EventHandlers();

    connectionFactory.setClosedCallback(eh);
    connectionFactory.setDisconnectedCallback(eh);
    connectionFactory.setExceptionHandler(eh);
    connectionFactory.setReconnectedCallback(eh);

    // invoke on startup here, so the user can override or set their
    // own callbacks in the plugin if need be.
    if (invokeOnStartup(connectionFactory) == false) {
        shutdown();
        throw new Exception("Startup failure initiated From plug-in");
    }

    connection = connectionFactory.createConnection();
    logger.debug("Connected to NATS cluster.");
}
 

private void setup() throws Exception {
    connectionFactory = new ConnectionFactory(properties);
    EventHandlers eh = new EventHandlers();

    connectionFactory.setClosedCallback(eh);
    connectionFactory.setDisconnectedCallback(eh);
    connectionFactory.setExceptionHandler(eh);
    connectionFactory.setReconnectedCallback(eh);

    // invoke on startup here, so the user can override or set their
    // own callbacks in the plugin if need be.
    if (invokeOnStartup(connectionFactory) == false) {
        shutdown();
        throw new Exception("Startup failure initiated From plug-in");
    }

    connection = connectionFactory.createConnection();
    logger.debug("Connected to NATS cluster.");
}
 

private void testConnectorAPIs() throws Exception {
    MessageHandler mh = new MessageHandler() {
        @Override
        public void onMessage(Message message) {
            ;;
        }
    };

    // test various combinatitions of subscribes and unsubscribes.
    connector.subscribe("foo1");
    connector.subscribe("foo1");

    connector.subscribe("foo2", mh);
    connector.subscribe("foo2", mh);

    connector.subscribe("foo3", "qg1");
    connector.subscribe("foo3", "qg1");

    connector.subscribe("foo4", "qg1", mh);
    connector.unsubscribe("foo1");
    connector.unsubscribe("foo2");
    connector.unsubscribe("foo3");

    connector.unsubscribe("foo4");
    connector.unsubscribe("foo4");

    connector.unsubscribe("unknown");
    connector.unsubscribe(null);

    connector.flush();

    Connection c = connector.getConnection();
    if (c == null)
        throw new Exception("Expected a valid connection.");

    ConnectionFactory cf = connector.getConnectionFactory();
    if (cf == null)
        throw new Exception("Expected a valid connection.");
}
 

private boolean invokeOnStartup(ConnectionFactory factory) {

        logger.debug("OnStartup");
        try {
            return plugin.onStartup(LoggerFactory.getLogger(plugin.getClass().getName()), factory);
        } catch (Exception e) {
            logger.error("Runtime exception thrown by plugin (OnStartup): ", e);
            return false;
        }
    }
 

private boolean invokeOnStartup(ConnectionFactory factory) {

        logger.debug("OnStartup");
        try {
            return plugin.onStartup(LoggerFactory.getLogger(plugin.getClass().getName()), factory);
        } catch (Exception e) {
            logger.error("Runtime exception thrown by plugin (OnStartup): ", e);
            return false;
        }
    }
 

private void testConnectorAPIs() throws Exception {
    MessageHandler mh = new MessageHandler() {
        @Override
        public void onMessage(Message message) {
            ;;
        }
    };

    // test various combinatitions of subscribes and unsubscribes.
    connector.subscribe("foo1");
    connector.subscribe("foo1");

    connector.subscribe("foo2", mh);
    connector.subscribe("foo2", mh);

    connector.subscribe("foo3", "qg1");
    connector.subscribe("foo3", "qg1");

    connector.subscribe("foo4", "qg1", mh);
    connector.unsubscribe("foo1");
    connector.unsubscribe("foo2");
    connector.unsubscribe("foo3");

    connector.unsubscribe("foo4");
    connector.unsubscribe("foo4");

    connector.unsubscribe("unknown");
    connector.unsubscribe(null);

    connector.flush();

    Connection c = connector.getConnection();
    if (c == null)
        throw new Exception("Expected a valid connection.");

    ConnectionFactory cf = connector.getConnectionFactory();
    if (cf == null)
        throw new Exception("Expected a valid connection.");
}
 

static synchronized Connection newDefaultConnection() throws IOException, TimeoutException {
    return new ConnectionFactory().createConnection();
}
 

public NatsClient(String... servers) {
    cf = new ConnectionFactory();
    cf.setServers(servers);
}
 

@Override
public boolean onStartup(Logger logger, ConnectionFactory factory) {
    this.logger = logger;
    return true;
}
 

@Override
public boolean onStartup(Logger logger, ConnectionFactory factory) {
    this.logger = logger;
    throw new RuntimeException("This is an exception from onStartup");
}
 

public ConnectionFactory getConnectionFactory() {
    return connectionFactory;
}
 

static synchronized Connection newDefaultConnection() throws IOException, TimeoutException {
    return new ConnectionFactory().createConnection();
}
 

@Override
public boolean onStartup(Logger logger, ConnectionFactory factory) {
    this.logger = logger;
    return true;
}
 

@Override
public boolean onStartup(Logger logger, ConnectionFactory factory) {
    this.logger = logger;
    throw new RuntimeException("This is an exception from onStartup");
}
 

public ConnectionFactory getConnectionFactory() {
    return connectionFactory;
}
 

public NATSObservableQueue(ConnectionFactory factory, String queueURI) {
    super(queueURI, "nats");
    this.fact = factory;
    open();
}
 

/**
 * Invoked when the connector is started up, before a connection
 * to the NATS cluster is made.  The NATS connection factory is
 * valid at this time, providing an opportunity to alter
 * NATS connection parameters based on other plugin variables.
 *
 * @param logger - logger for the NATS connector process.
 * @param factory - the NATS connection factory.
 * @return - true if the connector should continue, false otherwise.
 */
public boolean onStartup(Logger logger, ConnectionFactory factory);
 

/***
 * Advanced API to get the Connection Factory, This allows for NATS functionality beyond
 * the interface here.
 *
 * @return The NATS connector ConnectionFactory
 */
public ConnectionFactory getConnectionFactory();
 

/***
 * Advanced API to get the Connection Factory, This allows for NATS functionality beyond
 * the interface here.
 *
 * @return The NATS connector ConnectionFactory
 */
public ConnectionFactory getConnectionFactory();
 

/**
 * Invoked when the connector is started up, before a connection
 * to the NATS cluster is made.  The NATS connection factory is
 * valid at this time, providing an opportunity to alter
 * NATS connection parameters based on other plugin variables.
 *
 * @param logger - logger for the NATS connector process.
 * @param factory - the NATS connection factory.
 * @return - true if the connector should continue, false otherwise.
 */
public boolean onStartup(Logger logger, ConnectionFactory factory);