/*
* Copyright 2002-2007 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.aop.support;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.Serializable;
import java.util.HashSet;
import java.util.IdentityHashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import org.aopalliance.intercept.MethodInvocation;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.aop.IntroductionInfo;
import org.springframework.util.ClassUtils;
/**
* Support for implementations of {@link org.springframework.aop.IntroductionInfo}.
*
* <p>Allows subclasses to conveniently add all interfaces from a given object,
* and to suppress interfaces that should not be added. Also allows for querying
* all introduced interfaces.
*
* @author Rod Johnson
* @author Juergen Hoeller
*/
public class IntroductionInfoSupport implements IntroductionInfo, Serializable {
protected transient Log logger = LogFactory.getLog(getClass());
/** Set of interface Classes */
protected Set publishedInterfaces = new HashSet();
/**
* Methods that we know we should implement here: key is Method, value is Boolean.
**/
private transient Map rememberedMethods = createRememberedMethodMap();
/**
* Suppress the specified interface, which may have been autodetected
* due to the delegate implementing it. Call this method to exclude
* internal interfaces from being visible at the proxy level.
* <p>Does nothing if the interface is not implemented by the delegate.
* @param intf the interface to suppress
*/
public void suppressInterface(Class intf) {
this.publishedInterfaces.remove(intf);
}
public Class[] getInterfaces() {
return (Class[]) this.publishedInterfaces.toArray(new Class[this.publishedInterfaces.size()]);
}
/**
* Check whether the specified interfaces is a published introduction interface.
* @param intf the interface to check
* @return whether the interface is part of this introduction
*/
public boolean implementsInterface(Class intf) {
for (Iterator it = this.publishedInterfaces.iterator(); it.hasNext();) {
Class pubIntf = (Class) it.next();
if (intf.isInterface() && intf.isAssignableFrom(pubIntf)) {
return true;
}
}
return false;
}
/**
* Publish all interfaces that the given delegate implements at the proxy level.
* @param delegate the delegate object
*/
protected void implementInterfacesOnObject(Object delegate) {
this.publishedInterfaces.addAll(ClassUtils.getAllInterfacesAsSet(delegate));
}
private Map createRememberedMethodMap() {
return new IdentityHashMap(32);
}
/**
* Is this method on an introduced interface?
* @param mi the method invocation
* @return whether the invoked method is on an introduced interface
*/
protected final boolean isMethodOnIntroducedInterface(MethodInvocation mi) {
Boolean rememberedResult = (Boolean) this.rememberedMethods.get(mi.getMethod());
if (rememberedResult != null) {
return rememberedResult.booleanValue();
}
else {
// Work it out and cache it.
boolean result = implementsInterface(mi.getMethod().getDeclaringClass());
this.rememberedMethods.put(mi.getMethod(), (result ? Boolean.TRUE : Boolean.FALSE));
return result;
}
}
//---------------------------------------------------------------------
// Serialization support
//---------------------------------------------------------------------
/**
* This method is implemented only to restore the logger.
* We don't make the logger static as that would mean that subclasses
* would use this class's log category.
*/
private void readObject(ObjectInputStream ois) throws IOException, ClassNotFoundException {
// Rely on default serialization; just initialize state after deserialization.
ois.defaultReadObject();
// Initialize transient fields.
this.logger = LogFactory.getLog(getClass());
this.rememberedMethods = createRememberedMethodMap();
}
}