nats.client.spring.NatsFactoryBean.java Source code

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Here is the source code for nats.client.spring.NatsFactoryBean.java

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/*
 *   Copyright (c) 2013 Mike Heath.  All rights reserved.
 *
 *   Licensed under the Apache License, Version 2.0 (the "License");
 *   you may not use this file except in compliance with the License.
 *   You may obtain a copy of the License at
 *
 *       http://www.apache.org/licenses/LICENSE-2.0
 *
 *   Unless required by applicable law or agreed to in writing, software
 *   distributed under the License is distributed on an "AS IS" BASIS,
 *   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *   See the License for the specific language governing permissions and
 *   limitations under the License.
 *
 */
package nats.client.spring;

import io.netty.channel.EventLoopGroup;
import nats.NatsException;
import nats.client.ConnectionStateListener;
import nats.client.Message;
import nats.client.MessageHandler;
import nats.client.Nats;
import nats.client.NatsConnector;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.DisposableBean;
import org.springframework.beans.factory.FactoryBean;
import org.springframework.context.ApplicationEventPublisher;
import org.springframework.context.ApplicationEventPublisherAware;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Collection;
import java.util.concurrent.Executor;
import java.util.concurrent.TimeUnit;

/**
 * @author Mike Heath <elcapo@gmail.com>
 */
public class NatsFactoryBean implements FactoryBean<Nats>, DisposableBean, ApplicationEventPublisherAware {

    private static final Logger LOGGER = LoggerFactory.getLogger(NatsFactoryBean.class);

    private Nats nats;

    private Collection<String> hostUris;
    private boolean autoReconnect = true;
    private EventLoopGroup eventLoopGroup;
    private ConnectionStateListener connectionStateListener;
    private long reconnectWaitTime = -1;
    private Executor callbackExecutor;

    private Collection<SubscriptionConfig> subscriptions;

    private ApplicationEventPublisher applicationEventPublisher;

    @Override
    public Nats getObject() throws Exception {
        if (nats != null) {
            return nats;
        }
        LOGGER.debug("Creating NATS client");
        final NatsBuilder connector = new NatsBuilder(applicationEventPublisher);
        if (hostUris == null) {
            throw new IllegalStateException("At least one host URI must be provided.");
        }
        for (String uri : hostUris) {
            connector.addHost(uri);
        }
        connector.automaticReconnect(autoReconnect);
        if (connectionStateListener != null) {
            connector.addConnectionStateListener(connectionStateListener);
        }
        if (callbackExecutor != null) {
            connector.calllbackExecutor(callbackExecutor);
        }

        if (eventLoopGroup != null) {
            connector.eventLoopGroup(eventLoopGroup);
        }
        if (reconnectWaitTime >= 0) {
            connector.reconnectWaitTime(reconnectWaitTime, TimeUnit.MILLISECONDS);
        }
        nats = connector.connect();
        for (SubscriptionConfig subscription : subscriptions) {
            final Object bean = subscription.getBean();
            final Method method = bean.getClass().getMethod(subscription.getMethodName(), Message.class);
            nats.subscribe(subscription.getSubscription(), subscription.getQueueGroup())
                    .addMessageHandler(new MessageHandler() {
                        @Override
                        public void onMessage(Message message) {
                            try {
                                method.invoke(bean, message);
                            } catch (IllegalAccessException e) {
                                throw new Error(e);
                            } catch (InvocationTargetException e) {
                                throw new NatsException(e.getTargetException());
                            }
                        }
                    });
        }
        return nats;
    }

    @Override
    public Class<?> getObjectType() {
        return nats == null ? Nats.class : nats.getClass();
    }

    @Override
    public boolean isSingleton() {
        return true;
    }

    @Override
    public void destroy() throws Exception {
        if (nats != null) {
            LOGGER.debug("Closing NATS client.");
            nats.close();
        }
    }

    public void setHostUris(Collection<String> hostUris) {
        this.hostUris = new ArrayList<>(hostUris);
    }

    public void setAutoReconnect(boolean autoReconnect) {
        this.autoReconnect = autoReconnect;
    }

    public void setConnectionStateListener(ConnectionStateListener connectionStateListener) {
        this.connectionStateListener = connectionStateListener;
    }

    public void setEventLoopGroup(EventLoopGroup eventLoopGroup) {
        this.eventLoopGroup = eventLoopGroup;
    }

    public void setReconnectWaitTime(long reconnectWaitTime) {
        this.reconnectWaitTime = reconnectWaitTime;
    }

    public void setSubscriptions(Collection<SubscriptionConfig> subscriptions) {
        this.subscriptions = subscriptions;
    }

    public void setCallbackExecutor(Executor callbackExecutor) {
        this.callbackExecutor = callbackExecutor;
    }

    @Override
    public void setApplicationEventPublisher(ApplicationEventPublisher applicationEventPublisher) {
        this.applicationEventPublisher = applicationEventPublisher;
    }
}