org.springframework.context.weaving.AspectJWeavingEnabler 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.context.weaving;
import java.lang.instrument.ClassFileTransformer;
import java.lang.instrument.IllegalClassFormatException;
import java.security.ProtectionDomain;
import org.aspectj.weaver.loadtime.ClassPreProcessorAgentAdapter;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanClassLoaderAware;
import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.core.Ordered;
import org.springframework.instrument.classloading.InstrumentationLoadTimeWeaver;
import org.springframework.instrument.classloading.LoadTimeWeaver;
import org.springframework.lang.Nullable;
/**
* Post-processor that registers AspectJ's
* {@link org.aspectj.weaver.loadtime.ClassPreProcessorAgentAdapter}
* with the Spring application context's default
* {@link org.springframework.instrument.classloading.LoadTimeWeaver}.
*
* @author Juergen Hoeller
* @author Ramnivas Laddad
* @since 2.5
*/
public class AspectJWeavingEnabler
implements BeanFactoryPostProcessor, BeanClassLoaderAware, LoadTimeWeaverAware, Ordered {
/**
* The {@code aop.xml} resource location.
*/
public static final String ASPECTJ_AOP_XML_RESOURCE = "META-INF/aop.xml";
@Nullable
private ClassLoader beanClassLoader;
@Nullable
private LoadTimeWeaver loadTimeWeaver;
@Override
public void setBeanClassLoader(ClassLoader classLoader) {
this.beanClassLoader = classLoader;
}
@Override
public void setLoadTimeWeaver(LoadTimeWeaver loadTimeWeaver) {
this.loadTimeWeaver = loadTimeWeaver;
}
@Override
public int getOrder() {
return HIGHEST_PRECEDENCE;
}
@Override
public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
enableAspectJWeaving(this.loadTimeWeaver, this.beanClassLoader);
}
/**
* Enable AspectJ weaving with the given {@link LoadTimeWeaver}.
* @param weaverToUse the LoadTimeWeaver to apply to (or {@code null} for a default weaver)
* @param beanClassLoader the class loader to create a default weaver for (if necessary)
*/
public static void enableAspectJWeaving(
@Nullable LoadTimeWeaver weaverToUse, @Nullable ClassLoader beanClassLoader) {
if (weaverToUse == null) {
if (InstrumentationLoadTimeWeaver.isInstrumentationAvailable()) {
weaverToUse = new InstrumentationLoadTimeWeaver(beanClassLoader);
}
else {
throw new IllegalStateException("No LoadTimeWeaver available");
}
}
weaverToUse.addTransformer(
new AspectJClassBypassingClassFileTransformer(new ClassPreProcessorAgentAdapter()));
}
/**
* ClassFileTransformer decorator that suppresses processing of AspectJ
* classes in order to avoid potential LinkageErrors.
* @see org.springframework.context.annotation.LoadTimeWeavingConfiguration
*/
private static class AspectJClassBypassingClassFileTransformer implements ClassFileTransformer {
private final ClassFileTransformer delegate;
public AspectJClassBypassingClassFileTransformer(ClassFileTransformer delegate) {
this.delegate = delegate;
}
@Override
public byte[] transform(ClassLoader loader, String className, Class classBeingRedefined,
ProtectionDomain protectionDomain, byte[] classfileBuffer) throws IllegalClassFormatException {
if (className.startsWith("org.aspectj") || className.startsWith("org/aspectj")) {
return classfileBuffer;
}
return this.delegate.transform(loader, className, classBeingRedefined, protectionDomain, classfileBuffer);
}
}
}