org.springframework.aop.aspectj.annotation.ReflectiveAspectJAdvisorFactory Maven / Gradle / Ivy
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* Copyright 2002-2020 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
*
* https://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.io.Serializable;
import java.lang.annotation.Annotation;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Comparator;
import java.util.List;
import org.aopalliance.aop.Advice;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.AfterReturning;
import org.aspectj.lang.annotation.AfterThrowing;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.DeclareParents;
import org.aspectj.lang.annotation.Pointcut;
import org.springframework.aop.Advisor;
import org.springframework.aop.MethodBeforeAdvice;
import org.springframework.aop.aspectj.AbstractAspectJAdvice;
import org.springframework.aop.aspectj.AspectJAfterAdvice;
import org.springframework.aop.aspectj.AspectJAfterReturningAdvice;
import org.springframework.aop.aspectj.AspectJAfterThrowingAdvice;
import org.springframework.aop.aspectj.AspectJAroundAdvice;
import org.springframework.aop.aspectj.AspectJExpressionPointcut;
import org.springframework.aop.aspectj.AspectJMethodBeforeAdvice;
import org.springframework.aop.aspectj.DeclareParentsAdvisor;
import org.springframework.aop.framework.AopConfigException;
import org.springframework.aop.support.DefaultPointcutAdvisor;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.core.convert.converter.Converter;
import org.springframework.core.convert.converter.ConvertingComparator;
import org.springframework.lang.Nullable;
import org.springframework.util.ReflectionUtils;
import org.springframework.util.StringUtils;
import org.springframework.util.comparator.InstanceComparator;
/**
* Factory that can create Spring AOP Advisors given AspectJ classes from
* classes honoring AspectJ's annotation syntax, using reflection to invoke the
* corresponding advice methods.
*
* @author Rod Johnson
* @author Adrian Colyer
* @author Juergen Hoeller
* @author Ramnivas Laddad
* @author Phillip Webb
* @author Sam Brannen
* @since 2.0
*/
@SuppressWarnings("serial")
public class ReflectiveAspectJAdvisorFactory extends AbstractAspectJAdvisorFactory implements Serializable {
private static final Comparator METHOD_COMPARATOR;
static {
// Note: although @After is ordered before @AfterReturning and @AfterThrowing,
// an @After advice method will actually be invoked after @AfterReturning and
// @AfterThrowing methods due to the fact that AspectJAfterAdvice.invoke(MethodInvocation)
// invokes proceed() in a `try` block and only invokes the @After advice method
// in a corresponding `finally` block.
Comparator adviceKindComparator = new ConvertingComparator<>(
new InstanceComparator<>(
Around.class, Before.class, After.class, AfterReturning.class, AfterThrowing.class),
(Converter) method -> {
AspectJAnnotation ann = AbstractAspectJAdvisorFactory.findAspectJAnnotationOnMethod(method);
return (ann != null ? ann.getAnnotation() : null);
});
Comparator methodNameComparator = new ConvertingComparator<>(Method::getName);
METHOD_COMPARATOR = adviceKindComparator.thenComparing(methodNameComparator);
}
@Nullable
private final BeanFactory beanFactory;
/**
* Create a new {@code ReflectiveAspectJAdvisorFactory}.
*/
public ReflectiveAspectJAdvisorFactory() {
this(null);
}
/**
* Create a new {@code ReflectiveAspectJAdvisorFactory}, propagating the given
* {@link BeanFactory} to the created {@link AspectJExpressionPointcut} instances,
* for bean pointcut handling as well as consistent {@link ClassLoader} resolution.
* @param beanFactory the BeanFactory to propagate (may be {@code null}}
* @since 4.3.6
* @see AspectJExpressionPointcut#setBeanFactory
* @see org.springframework.beans.factory.config.ConfigurableBeanFactory#getBeanClassLoader()
*/
public ReflectiveAspectJAdvisorFactory(@Nullable BeanFactory beanFactory) {
this.beanFactory = beanFactory;
}
@Override
public List getAdvisors(MetadataAwareAspectInstanceFactory aspectInstanceFactory) {
Class aspectClass = aspectInstanceFactory.getAspectMetadata().getAspectClass();
String aspectName = aspectInstanceFactory.getAspectMetadata().getAspectName();
validate(aspectClass);
// We need to wrap the MetadataAwareAspectInstanceFactory with a decorator
// so that it will only instantiate once.
MetadataAwareAspectInstanceFactory lazySingletonAspectInstanceFactory =
new LazySingletonAspectInstanceFactoryDecorator(aspectInstanceFactory);
List advisors = new ArrayList<>();
for (Method method : getAdvisorMethods(aspectClass)) {
// Prior to Spring Framework 5.2.7, advisors.size() was supplied as the declarationOrderInAspect
// to getAdvisor(...) to represent the "current position" in the declared methods list.
// However, since Java 7 the "current position" is not valid since the JDK no longer
// returns declared methods in the order in which they are declared in the source code.
// Thus, we now hard code the declarationOrderInAspect to 0 for all advice methods
// discovered via reflection in order to support reliable advice ordering across JVM launches.
// Specifically, a value of 0 aligns with the default value used in
// AspectJPrecedenceComparator.getAspectDeclarationOrder(Advisor).
Advisor advisor = getAdvisor(method, lazySingletonAspectInstanceFactory, 0, aspectName);
if (advisor != null) {
advisors.add(advisor);
}
}
// If it's a per target aspect, emit the dummy instantiating aspect.
if (!advisors.isEmpty() && lazySingletonAspectInstanceFactory.getAspectMetadata().isLazilyInstantiated()) {
Advisor instantiationAdvisor = new SyntheticInstantiationAdvisor(lazySingletonAspectInstanceFactory);
advisors.add(0, instantiationAdvisor);
}
// Find introduction fields.
for (Field field : aspectClass.getDeclaredFields()) {
Advisor advisor = getDeclareParentsAdvisor(field);
if (advisor != null) {
advisors.add(advisor);
}
}
return advisors;
}
private List getAdvisorMethods(Class aspectClass) {
final List methods = new ArrayList<>();
ReflectionUtils.doWithMethods(aspectClass, method -> {
// Exclude pointcuts
if (AnnotationUtils.getAnnotation(method, Pointcut.class) == null) {
methods.add(method);
}
}, ReflectionUtils.USER_DECLARED_METHODS);
if (methods.size() > 1) {
methods.sort(METHOD_COMPARATOR);
}
return methods;
}
/**
* Build a {@link org.springframework.aop.aspectj.DeclareParentsAdvisor}
* for the given introduction field.
* Resulting Advisors will need to be evaluated for targets.
* @param introductionField the field to introspect
* @return the Advisor instance, or {@code null} if not an Advisor
*/
@Nullable
private Advisor getDeclareParentsAdvisor(Field introductionField) {
DeclareParents declareParents = introductionField.getAnnotation(DeclareParents.class);
if (declareParents == null) {
// Not an introduction field
return null;
}
if (DeclareParents.class == declareParents.defaultImpl()) {
throw new IllegalStateException("'defaultImpl' attribute must be set on DeclareParents");
}
return new DeclareParentsAdvisor(
introductionField.getType(), declareParents.value(), declareParents.defaultImpl());
}
@Override
@Nullable
public Advisor getAdvisor(Method candidateAdviceMethod, MetadataAwareAspectInstanceFactory aspectInstanceFactory,
int declarationOrderInAspect, String aspectName) {
validate(aspectInstanceFactory.getAspectMetadata().getAspectClass());
AspectJExpressionPointcut expressionPointcut = getPointcut(
candidateAdviceMethod, aspectInstanceFactory.getAspectMetadata().getAspectClass());
if (expressionPointcut == null) {
return null;
}
return new InstantiationModelAwarePointcutAdvisorImpl(expressionPointcut, candidateAdviceMethod,
this, aspectInstanceFactory, declarationOrderInAspect, aspectName);
}
@Nullable
private AspectJExpressionPointcut getPointcut(Method candidateAdviceMethod, Class candidateAspectClass) {
AspectJAnnotation aspectJAnnotation =
AbstractAspectJAdvisorFactory.findAspectJAnnotationOnMethod(candidateAdviceMethod);
if (aspectJAnnotation == null) {
return null;
}
AspectJExpressionPointcut ajexp =
new AspectJExpressionPointcut(candidateAspectClass, new String[0], new Class[0]);
ajexp.setExpression(aspectJAnnotation.getPointcutExpression());
if (this.beanFactory != null) {
ajexp.setBeanFactory(this.beanFactory);
}
return ajexp;
}
@Override
@Nullable
public Advice getAdvice(Method candidateAdviceMethod, AspectJExpressionPointcut expressionPointcut,
MetadataAwareAspectInstanceFactory aspectInstanceFactory, int declarationOrder, String aspectName) {
Class candidateAspectClass = aspectInstanceFactory.getAspectMetadata().getAspectClass();
validate(candidateAspectClass);
AspectJAnnotation aspectJAnnotation =
AbstractAspectJAdvisorFactory.findAspectJAnnotationOnMethod(candidateAdviceMethod);
if (aspectJAnnotation == null) {
return null;
}
// If we get here, we know we have an AspectJ method.
// Check that it's an AspectJ-annotated class
if (!isAspect(candidateAspectClass)) {
throw new AopConfigException("Advice must be declared inside an aspect type: " +
"Offending method '" + candidateAdviceMethod + "' in class [" +
candidateAspectClass.getName() + "]");
}
if (logger.isDebugEnabled()) {
logger.debug("Found AspectJ method: " + candidateAdviceMethod);
}
AbstractAspectJAdvice springAdvice;
switch (aspectJAnnotation.getAnnotationType()) {
case AtPointcut:
if (logger.isDebugEnabled()) {
logger.debug("Processing pointcut '" + candidateAdviceMethod.getName() + "'");
}
return null;
case AtAround:
springAdvice = new AspectJAroundAdvice(
candidateAdviceMethod, expressionPointcut, aspectInstanceFactory);
break;
case AtBefore:
springAdvice = new AspectJMethodBeforeAdvice(
candidateAdviceMethod, expressionPointcut, aspectInstanceFactory);
break;
case AtAfter:
springAdvice = new AspectJAfterAdvice(
candidateAdviceMethod, expressionPointcut, aspectInstanceFactory);
break;
case AtAfterReturning:
springAdvice = new AspectJAfterReturningAdvice(
candidateAdviceMethod, expressionPointcut, aspectInstanceFactory);
AfterReturning afterReturningAnnotation = (AfterReturning) aspectJAnnotation.getAnnotation();
if (StringUtils.hasText(afterReturningAnnotation.returning())) {
springAdvice.setReturningName(afterReturningAnnotation.returning());
}
break;
case AtAfterThrowing:
springAdvice = new AspectJAfterThrowingAdvice(
candidateAdviceMethod, expressionPointcut, aspectInstanceFactory);
AfterThrowing afterThrowingAnnotation = (AfterThrowing) aspectJAnnotation.getAnnotation();
if (StringUtils.hasText(afterThrowingAnnotation.throwing())) {
springAdvice.setThrowingName(afterThrowingAnnotation.throwing());
}
break;
default:
throw new UnsupportedOperationException(
"Unsupported advice type on method: " + candidateAdviceMethod);
}
// Now to configure the advice...
springAdvice.setAspectName(aspectName);
springAdvice.setDeclarationOrder(declarationOrder);
String[] argNames = this.parameterNameDiscoverer.getParameterNames(candidateAdviceMethod);
if (argNames != null) {
springAdvice.setArgumentNamesFromStringArray(argNames);
}
springAdvice.calculateArgumentBindings();
return springAdvice;
}
/**
* Synthetic advisor that instantiates the aspect.
* Triggered by per-clause pointcut on non-singleton aspect.
* The advice has no effect.
*/
@SuppressWarnings("serial")
protected static class SyntheticInstantiationAdvisor extends DefaultPointcutAdvisor {
public SyntheticInstantiationAdvisor(final MetadataAwareAspectInstanceFactory aif) {
super(aif.getAspectMetadata().getPerClausePointcut(), (MethodBeforeAdvice)
(method, args, target) -> aif.getAspectInstance());
}
}
}