org.springframework.messaging.support.AbstractSubscribableChannel Maven / Gradle / Ivy
/*
* Copyright 2002-2016 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.messaging.support;
import java.util.Collections;
import java.util.Set;
import java.util.concurrent.CopyOnWriteArraySet;
import org.springframework.messaging.MessageHandler;
import org.springframework.messaging.SubscribableChannel;
/**
* Abstract base class for {@link SubscribableChannel} implementations.
*
* @author Rossen Stoyanchev
* @since 4.0
*/
public abstract class AbstractSubscribableChannel extends AbstractMessageChannel implements SubscribableChannel {
private final Set handlers = new CopyOnWriteArraySet<>();
public Set getSubscribers() {
return Collections.unmodifiableSet(this.handlers);
}
public boolean hasSubscription(MessageHandler handler) {
return this.handlers.contains(handler);
}
@Override
public boolean subscribe(MessageHandler handler) {
boolean result = this.handlers.add(handler);
if (result) {
if (logger.isDebugEnabled()) {
logger.debug(getBeanName() + " added " + handler);
}
}
return result;
}
@Override
public boolean unsubscribe(MessageHandler handler) {
boolean result = this.handlers.remove(handler);
if (result) {
if (logger.isDebugEnabled()) {
logger.debug(getBeanName() + " removed " + handler);
}
}
return result;
}
}