/*
* Copyright 2002-2013 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.context.annotation;
import org.springframework.beans.factory.BeanClassLoaderAware;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.context.annotation.EnableLoadTimeWeaving.AspectJWeaving;
import org.springframework.context.weaving.AspectJWeavingEnabler;
import org.springframework.context.weaving.DefaultContextLoadTimeWeaver;
import org.springframework.core.annotation.AnnotationAttributes;
import org.springframework.core.type.AnnotationMetadata;
import org.springframework.instrument.classloading.LoadTimeWeaver;
import org.springframework.util.Assert;
import static org.springframework.context.weaving.AspectJWeavingEnabler.*;
/**
* {@code @Configuration} class that registers a {@link LoadTimeWeaver} bean.
*
* <p>This configuration class is automatically imported when using the
* {@link EnableLoadTimeWeaving} annotation. See {@code @EnableLoadTimeWeaving}
* javadoc for complete usage details.
*
* @author Chris Beams
* @since 3.1
* @see LoadTimeWeavingConfigurer
* @see ConfigurableApplicationContext#LOAD_TIME_WEAVER_BEAN_NAME
*/
@Configuration
public class LoadTimeWeavingConfiguration implements ImportAware, BeanClassLoaderAware {
private AnnotationAttributes enableLTW;
@Autowired(required=false)
private LoadTimeWeavingConfigurer ltwConfigurer;
private ClassLoader beanClassLoader;
@Override
public void setImportMetadata(AnnotationMetadata importMetadata) {
this.enableLTW = AnnotationConfigUtils.attributesFor(importMetadata, EnableLoadTimeWeaving.class);
Assert.notNull(this.enableLTW,
"@EnableLoadTimeWeaving is not present on importing class " + importMetadata.getClassName());
}
@Override
public void setBeanClassLoader(ClassLoader beanClassLoader) {
this.beanClassLoader = beanClassLoader;
}
@Bean(name=ConfigurableApplicationContext.LOAD_TIME_WEAVER_BEAN_NAME)
@Role(BeanDefinition.ROLE_INFRASTRUCTURE)
public LoadTimeWeaver loadTimeWeaver() {
LoadTimeWeaver loadTimeWeaver = null;
if (this.ltwConfigurer != null) {
// the user has provided a custom LTW instance
loadTimeWeaver = ltwConfigurer.getLoadTimeWeaver();
}
if (loadTimeWeaver == null) {
// no custom LTW provided -> fall back to the default
loadTimeWeaver = new DefaultContextLoadTimeWeaver(this.beanClassLoader);
}
AspectJWeaving aspectJWeaving = this.enableLTW.getEnum("aspectjWeaving");
switch (aspectJWeaving) {
case DISABLED:
// AJ weaving is disabled -> do nothing
break;
case AUTODETECT:
if (this.beanClassLoader.getResource(ASPECTJ_AOP_XML_RESOURCE) == null) {
// No aop.xml present on the classpath -> treat as 'disabled'
break;
}
// aop.xml is present on the classpath -> enable
AspectJWeavingEnabler.enableAspectJWeaving(loadTimeWeaver, this.beanClassLoader);
break;
case ENABLED:
AspectJWeavingEnabler.enableAspectJWeaving(loadTimeWeaver, this.beanClassLoader);
break;
}
return loadTimeWeaver;
}
}