Spring Framework example source code file (InstantiationModelAwarePointcutAdvisorImpl.java)

This example Spring Framework source code file (InstantiationModelAwarePointcutAdvisorImpl.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Spring Framework tags/keywords

advice, aspectjexpressionpointcut, aspectjexpressionpointcut, boolean, instantiationmodelawarepointcutadvisor, instantiationmodelawarepointcutadvisorimpl, lazysingletonaspectinstancefactorydecorator, metadataawareaspectinstancefactory, metadataawareaspectinstancefactory, override, pointcut, pointcut, reflection, string, string

The Spring Framework InstantiationModelAwarePointcutAdvisorImpl.java source code

/*
 * 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.aspectj.annotation;

import java.lang.reflect.Method;

import org.aopalliance.aop.Advice;
import org.aspectj.lang.reflect.PerClauseKind;

import org.springframework.aop.Pointcut;
import org.springframework.aop.aspectj.AspectJExpressionPointcut;
import org.springframework.aop.aspectj.AspectJPrecedenceInformation;
import org.springframework.aop.aspectj.InstantiationModelAwarePointcutAdvisor;
import org.springframework.aop.aspectj.annotation.AbstractAspectJAdvisorFactory.AspectJAnnotation;
import org.springframework.aop.support.DynamicMethodMatcherPointcut;
import org.springframework.aop.support.Pointcuts;

/**
 * Internal implementation of AspectJPointcutAdvisor.
 * Note that there will be one instance of this advisor for each target method.
 *
 * @author Rod Johnson
 * @author Juergen Hoeller
 * @since 2.0
 */
class InstantiationModelAwarePointcutAdvisorImpl
		implements InstantiationModelAwarePointcutAdvisor, AspectJPrecedenceInformation {

	private final AspectJExpressionPointcut declaredPointcut;
	
	private Pointcut pointcut;
	
	private final MetadataAwareAspectInstanceFactory aspectInstanceFactory;
	
	private final Method method;
	
	private final boolean lazy;
	
	private final AspectJAdvisorFactory atAspectJAdvisorFactory;
	
	private Advice instantiatedAdvice;

	private int declarationOrder;
	
	private String aspectName;
	
	private Boolean isBeforeAdvice = null;

	private Boolean isAfterAdvice = null;


	public InstantiationModelAwarePointcutAdvisorImpl(
			AspectJAdvisorFactory af, 
			AspectJExpressionPointcut ajexp, 
			MetadataAwareAspectInstanceFactory aif, 
			Method method,
			int declarationOrderInAspect,
			String aspectName) {

		this.declaredPointcut = ajexp;
		this.method = method;
		this.atAspectJAdvisorFactory = af;
		this.aspectInstanceFactory = aif;
		this.declarationOrder = declarationOrderInAspect;
		this.aspectName = aspectName;
		
		if (aif.getAspectMetadata().isLazilyInstantiated()) {
			// Static part of the pointcut is a lazy type.
			Pointcut preInstantiationPointcut =
					Pointcuts.union(aif.getAspectMetadata().getPerClausePointcut(), this.declaredPointcut);
			
			// Make it dynamic: must mutate from pre-instantiation to post-instantiation state.
			// If it's not a dynamic pointcut, it may be optimized out
			// by the Spring AOP infrastructure after the first evaluation.
			this.pointcut = new PerTargetInstantiationModelPointcut(this.declaredPointcut, preInstantiationPointcut, aif);
			this.lazy = true;
		}
		else {
			// A singleton aspect.
			this.instantiatedAdvice = instantiateAdvice(this.declaredPointcut);
			this.pointcut = declaredPointcut;
			this.lazy = false;
		}
	}


	/**
	 * The pointcut for Spring AOP to use. Actual behaviour of the pointcut will change
	 * depending on the state of the advice.
	 */
	public Pointcut getPointcut() {
		return this.pointcut;
	}

	/**
	 * This is only of interest for Spring AOP: AspectJ instantiation semantics
	 * are much richer. In AspectJ terminology, all a return of <code>true
	 * means here is that the aspect is not a SINGLETON.
	 */
	public boolean isPerInstance() {
		return (getAspectMetadata().getAjType().getPerClause().getKind() != PerClauseKind.SINGLETON);
	}
	
	/**
	 * Return the AspectJ AspectMetadata for this advisor.
	 */
	public AspectMetadata getAspectMetadata() {
		return this.aspectInstanceFactory.getAspectMetadata();
	}

	/**
	 * Lazily instantiate advice if necessary.
	 */
	public synchronized Advice getAdvice() {
		if (this.instantiatedAdvice == null) {
			this.instantiatedAdvice = instantiateAdvice(this.declaredPointcut);
		}
		return this.instantiatedAdvice;
	}
	
	public boolean isLazy() {
		return this.lazy;
	}

	public synchronized boolean isAdviceInstantiated() {
		return (this.instantiatedAdvice != null);
	}


	private Advice instantiateAdvice(AspectJExpressionPointcut pcut) {
		return this.atAspectJAdvisorFactory.getAdvice(
				this.method, pcut, this.aspectInstanceFactory, this.declarationOrder, this.aspectName);
	}
	
	public MetadataAwareAspectInstanceFactory getAspectInstanceFactory() {
		return this.aspectInstanceFactory;
	}

	public AspectJExpressionPointcut getDeclaredPointcut() {
		return this.declaredPointcut;
	}

	public int getOrder() {
		return this.aspectInstanceFactory.getOrder();
	}

	public String getAspectName() {
		return this.aspectName;
	}

	public int getDeclarationOrder() {
		return this.declarationOrder;
	}

	public boolean isBeforeAdvice() {
		if (this.isBeforeAdvice == null) {
			determineAdviceType();
		}
		return this.isBeforeAdvice;
	}

	public boolean isAfterAdvice() {
		if (this.isAfterAdvice == null) {
			determineAdviceType();
		}
		return this.isAfterAdvice;
	}

	/**
	 * Duplicates some logic from getAdvice, but importantly does not force
	 * creation of the advice.
	 */
	private void determineAdviceType() {
		AspectJAnnotation<?> aspectJAnnotation =
				AbstractAspectJAdvisorFactory.findAspectJAnnotationOnMethod(this.method);
		if (aspectJAnnotation == null) {
			this.isBeforeAdvice = false;
			this.isAfterAdvice = false;
		}
		else {
			switch (aspectJAnnotation.getAnnotationType()) {
				case AtAfter:
				case AtAfterReturning:
				case AtAfterThrowing:
					this.isAfterAdvice = true;
					this.isBeforeAdvice = false;
					break;
				case AtAround:
				case AtPointcut:
					this.isAfterAdvice = false;
					this.isBeforeAdvice = false;
					break;
				case AtBefore:
					this.isAfterAdvice = false;
					this.isBeforeAdvice = true;
			}
		}
	}


	@Override
	public String toString() {
		return "InstantiationModelAwarePointcutAdvisor: expression [" + getDeclaredPointcut().getExpression() +
			"]; advice method [" + this.method + "]; perClauseKind=" +
			this.aspectInstanceFactory.getAspectMetadata().getAjType().getPerClause().getKind();

	}


	/**
	 * Pointcut implementation that changes its behaviour when the advice is instantiated.
	 * Note that this is a <i>dynamic pointcut. Otherwise it might
	 * be optimized out if it does not at first match statically.
	 */
	private class PerTargetInstantiationModelPointcut extends DynamicMethodMatcherPointcut {

		private final AspectJExpressionPointcut declaredPointcut;

		private final Pointcut preInstantiationPointcut;

		private LazySingletonAspectInstanceFactoryDecorator aspectInstanceFactory;

		private PerTargetInstantiationModelPointcut(AspectJExpressionPointcut declaredPointcut,
				Pointcut preInstantiationPointcut, MetadataAwareAspectInstanceFactory aspectInstanceFactory) {
			this.declaredPointcut = declaredPointcut;
			this.preInstantiationPointcut = preInstantiationPointcut;
			if (aspectInstanceFactory instanceof LazySingletonAspectInstanceFactoryDecorator) {
				this.aspectInstanceFactory = (LazySingletonAspectInstanceFactoryDecorator) aspectInstanceFactory;
			}
		}

		@Override
		public boolean matches(Method method, Class targetClass) {
			// We're either instantiated and matching on declared pointcut, or uninstantiated matching on either pointcut
			return (isAspectMaterialized() && this.declaredPointcut.matches(method, targetClass)) ||
					this.preInstantiationPointcut.getMethodMatcher().matches(method, targetClass);
		}

		public boolean matches(Method method, Class targetClass, Object[] args) {
			// This can match only on declared pointcut.
			return (isAspectMaterialized() && this.declaredPointcut.matches(method, targetClass));
		}

		private boolean isAspectMaterialized() {
			return (this.aspectInstanceFactory == null || this.aspectInstanceFactory.isMaterialized());
		}
	}

}