/*
* Copyright 2002-2009 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.context.event;
import org.springframework.aop.support.AopUtils;
import org.springframework.context.ApplicationEvent;
import org.springframework.context.ApplicationListener;
import org.springframework.core.GenericTypeResolver;
import org.springframework.core.Ordered;
import org.springframework.util.Assert;
/**
* {@link SmartApplicationListener} adapter that determines supported event types
* through introspecting the generically declared type of the target listener.
*
* @author Juergen Hoeller
* @since 3.0
* @see org.springframework.context.ApplicationListener#onApplicationEvent
*/
public class GenericApplicationListenerAdapter implements SmartApplicationListener {
private final ApplicationListener delegate;
/**
* Create a new GenericApplicationListener for the given delegate.
* @param delegate the delegate listener to be invoked
*/
public GenericApplicationListenerAdapter(ApplicationListener delegate) {
Assert.notNull(delegate, "Delegate listener must not be null");
this.delegate = delegate;
}
@SuppressWarnings("unchecked")
public void onApplicationEvent(ApplicationEvent event) {
this.delegate.onApplicationEvent(event);
}
public boolean supportsEventType(Class<? extends ApplicationEvent> eventType) {
Class typeArg = GenericTypeResolver.resolveTypeArgument(this.delegate.getClass(), ApplicationListener.class);
if (typeArg == null || typeArg.equals(ApplicationEvent.class)) {
Class targetClass = AopUtils.getTargetClass(this.delegate);
if (targetClass != this.delegate.getClass()) {
typeArg = GenericTypeResolver.resolveTypeArgument(targetClass, ApplicationListener.class);
}
}
return (typeArg == null || typeArg.isAssignableFrom(eventType));
}
public boolean supportsSourceType(Class<?> sourceType) {
return true;
}
public int getOrder() {
return (this.delegate instanceof Ordered ? ((Ordered) this.delegate).getOrder() : Ordered.LOWEST_PRECEDENCE);
}
}
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