org.springframework.aop.support.IntroductionInfoSupport.java Source code

Introduction

Here is the source code for org.springframework.aop.support.IntroductionInfoSupport.java

Source

/*
 * Copyright 2002-2006 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.Iterator;
import java.util.Set;

import org.aopalliance.aop.AspectException;
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
 */
public class IntroductionInfoSupport implements IntroductionInfo, Serializable {

    protected transient Log logger = LogFactory.getLog(getClass());

    /** Set of Class */
    protected Set publishedInterfaces = new HashSet();

    /**
     * Suppress the specified interface, which will have been
     * autodetected due to its implementation by the delegate.
     * Does nothing if it's not implemented by the delegate.
     * @param intf 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()]);
    }

    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;
    }

    protected void implementInterfacesOnObject(Object delegate) {
        this.publishedInterfaces.addAll(ClassUtils.getAllInterfacesAsSet(delegate));
    }

    /**
     * Is this method on an introduced interface?
     * @param mi method invocation
     * @return whether the method is on an introduced interface
     */
    protected final boolean isMethodOnIntroducedInterface(MethodInvocation mi) {
        return implementsInterface(mi.getMethod().getDeclaringClass());
    }

    /**
     * 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 {
        // Rely on default serialization, just initialize state after deserialization.
        try {
            ois.defaultReadObject();
        } catch (ClassNotFoundException ex) {
            throw new AspectException("Failed to deserialize Spring DelegatingIntroductionInterceptor: "
                    + "Check that Spring AOP libraries and implementation class for the introduction are "
                    + "available on the client side. " + ex);
        }
        // Initialize transient fields.
        this.logger = LogFactory.getLog(getClass());
    }

}