org.springframework.aop.aspectj.annotation.BeanFactoryAspectInstanceFactory Maven / Gradle / Ivy
/*
* Copyright 2002-2018 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 org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.config.ConfigurableBeanFactory;
import org.springframework.core.Ordered;
import org.springframework.core.annotation.OrderUtils;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
/**
* {@link org.springframework.aop.aspectj.AspectInstanceFactory} implementation
* backed by a Spring {@link org.springframework.beans.factory.BeanFactory}.
*
* Note that this may instantiate multiple times if using a prototype,
* which probably won't give the semantics you expect.
* Use a {@link LazySingletonAspectInstanceFactoryDecorator}
* to wrap this to ensure only one new aspect comes back.
*
* @author Rod Johnson
* @author Juergen Hoeller
* @since 2.0
* @see org.springframework.beans.factory.BeanFactory
* @see LazySingletonAspectInstanceFactoryDecorator
*/
@SuppressWarnings("serial")
public class BeanFactoryAspectInstanceFactory implements MetadataAwareAspectInstanceFactory, Serializable {
private final BeanFactory beanFactory;
private final String name;
private final AspectMetadata aspectMetadata;
/**
* Create a BeanFactoryAspectInstanceFactory. AspectJ will be called to
* introspect to create AJType metadata using the type returned for the
* given bean name from the BeanFactory.
* @param beanFactory the BeanFactory to obtain instance(s) from
* @param name the name of the bean
*/
public BeanFactoryAspectInstanceFactory(BeanFactory beanFactory, String name) {
this(beanFactory, name, null);
}
/**
* Create a BeanFactoryAspectInstanceFactory, providing a type that AspectJ should
* introspect to create AJType metadata. Use if the BeanFactory may consider the type
* to be a subclass (as when using CGLIB), and the information should relate to a superclass.
* @param beanFactory the BeanFactory to obtain instance(s) from
* @param name the name of the bean
* @param type the type that should be introspected by AspectJ
* ({@code null} indicates resolution through {@link BeanFactory#getType} via the bean name)
*/
public BeanFactoryAspectInstanceFactory(BeanFactory beanFactory, String name, @Nullable Class type) {
Assert.notNull(beanFactory, "BeanFactory must not be null");
Assert.notNull(name, "Bean name must not be null");
this.beanFactory = beanFactory;
this.name = name;
Class resolvedType = type;
if (type == null) {
resolvedType = beanFactory.getType(name);
Assert.notNull(resolvedType, "Unresolvable bean type - explicitly specify the aspect class");
}
this.aspectMetadata = new AspectMetadata(resolvedType, name);
}
@Override
public Object getAspectInstance() {
return this.beanFactory.getBean(this.name);
}
@Override
@Nullable
public ClassLoader getAspectClassLoader() {
return (this.beanFactory instanceof ConfigurableBeanFactory ?
((ConfigurableBeanFactory) this.beanFactory).getBeanClassLoader() :
ClassUtils.getDefaultClassLoader());
}
@Override
public AspectMetadata getAspectMetadata() {
return this.aspectMetadata;
}
@Override
@Nullable
public Object getAspectCreationMutex() {
if (this.beanFactory.isSingleton(this.name)) {
// Rely on singleton semantics provided by the factory -> no local lock.
return null;
}
else if (this.beanFactory instanceof ConfigurableBeanFactory) {
// No singleton guarantees from the factory -> let's lock locally but
// reuse the factory's singleton lock, just in case a lazy dependency
// of our advice bean happens to trigger the singleton lock implicitly...
return ((ConfigurableBeanFactory) this.beanFactory).getSingletonMutex();
}
else {
return this;
}
}
/**
* Determine the order for this factory's target aspect, either
* an instance-specific order expressed through implementing the
* {@link org.springframework.core.Ordered} interface (only
* checked for singleton beans), or an order expressed through the
* {@link org.springframework.core.annotation.Order} annotation
* at the class level.
* @see org.springframework.core.Ordered
* @see org.springframework.core.annotation.Order
*/
@Override
public int getOrder() {
Class type = this.beanFactory.getType(this.name);
if (type != null) {
if (Ordered.class.isAssignableFrom(type) && this.beanFactory.isSingleton(this.name)) {
return ((Ordered) this.beanFactory.getBean(this.name)).getOrder();
}
return OrderUtils.getOrder(type, Ordered.LOWEST_PRECEDENCE);
}
return Ordered.LOWEST_PRECEDENCE;
}
@Override
public String toString() {
return getClass().getSimpleName() + ": bean name '" + this.name + "'";
}
}