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/* * Copyright 2002-2013 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.channel; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.beans.factory.BeanNameAware; import org.springframework.messaging.Message; import org.springframework.messaging.MessageHandler; import org.springframework.messaging.SubscribableChannel; import org.springframework.util.Assert; import org.springframework.util.ObjectUtils; /** * Abstract base class for {@link SubscribableChannel} implementations. * * @author Rossen Stoyanchev * @since 4.0 */ public abstract class AbstractSubscribableChannel implements SubscribableChannel, BeanNameAware { protected Log logger = LogFactory.getLog(getClass()); private String beanName; public AbstractSubscribableChannel() { this.beanName = getClass().getSimpleName() + "@" + ObjectUtils.getIdentityHexString(this); } /** * {@inheritDoc} * <p>Used primarily for logging purposes. */ @Override public void setBeanName(String name) { this.beanName = name; } /** * @return the name for this channel. */ public String getBeanName() { return this.beanName; } @Override public final boolean send(Message<?> message) { return send(message, INDEFINITE_TIMEOUT); } @Override public final boolean send(Message<?> message, long timeout) { Assert.notNull(message, "Message must not be null"); if (logger.isTraceEnabled()) { logger.trace("[" + this.beanName + "] sending message " + message); } return sendInternal(message, timeout); } protected abstract boolean sendInternal(Message<?> message, long timeout); @Override public final boolean subscribe(MessageHandler handler) { if (hasSubscription(handler)) { logger.warn("[" + this.beanName + "] handler already subscribed " + handler); return false; } if (logger.isDebugEnabled()) { logger.debug("[" + this.beanName + "] subscribing " + handler); } return subscribeInternal(handler); } protected abstract boolean hasSubscription(MessageHandler handler); protected abstract boolean subscribeInternal(MessageHandler handler); @Override public final boolean unsubscribe(MessageHandler handler) { if (logger.isDebugEnabled()) { logger.debug("[" + this.beanName + "] unsubscribing " + handler); } return unsubscribeInternal(handler); } protected abstract boolean unsubscribeInternal(MessageHandler handler); }