/*
* Copyright 2002-2014 the original author or authors.
*
* 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 org.springframework.integration.channel;
import org.springframework.integration.context.IntegrationProperties;
import org.springframework.integration.dispatcher.LoadBalancingStrategy;
import org.springframework.integration.dispatcher.RoundRobinLoadBalancingStrategy;
import org.springframework.integration.dispatcher.UnicastingDispatcher;
/**
* A channel that invokes a single subscriber for each sent Message.
* The invocation will occur in the sender's thread.
*
* @author Dave Syer
* @author Mark Fisher
* @author Iwein Fuld
* @author Oleg Zhurakousky
* @author Gary Russell
*/
public class DirectChannel extends AbstractSubscribableChannel {
private final UnicastingDispatcher dispatcher = new UnicastingDispatcher();
private volatile Integer maxSubscribers;
/**
* Create a channel with default {@link RoundRobinLoadBalancingStrategy}
*/
public DirectChannel() {
this(new RoundRobinLoadBalancingStrategy());
}
/**
* Create a DirectChannel with a {@link LoadBalancingStrategy}. The
* strategy <em>must not</em> be null.
*
* @param loadBalancingStrategy The load balancing strategy implementation.
*/
public DirectChannel(LoadBalancingStrategy loadBalancingStrategy) {
this.dispatcher.setLoadBalancingStrategy(loadBalancingStrategy);
}
/**
* Specify whether the channel's dispatcher should have failover enabled.
* By default, it will. Set this value to 'false' to disable it.
*
* @param failover The failover boolean.
*/
public void setFailover(boolean failover) {
this.dispatcher.setFailover(failover);
}
/**
* Specify the maximum number of subscribers supported by the
* channel's dispatcher.
*
* @param maxSubscribers The maximum number of subscribers allowed.
*/
public void setMaxSubscribers(int maxSubscribers) {
this.maxSubscribers = maxSubscribers;
this.dispatcher.setMaxSubscribers(maxSubscribers);
}
@Override
protected UnicastingDispatcher getDispatcher() {
return this.dispatcher;
}
@Override
protected void onInit() throws Exception {
super.onInit();
if (this.maxSubscribers == null) {
Integer maxSubscribers = this.getIntegrationProperty(IntegrationProperties.CHANNELS_MAX_UNICAST_SUBSCRIBERS, Integer.class);
this.setMaxSubscribers(maxSubscribers);
}
}
}