Spring-14 AOP 代理对象源码

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本章会介绍 AOP 生成的代理对象源码，让读者更加清晰的认识 spring AOP 创建的代理对象。

场景

public class AopExp1 {

    public static void main(String[] args) throws Exception {

        LoggerContext loggerContext = (LoggerContext) LoggerFactory.getILoggerFactory();
        Logger logger = loggerContext.getLogger(AnnotationAwareAspectJAutoProxyCreator.class);
        logger.setLevel(Level.TRACE);

        DefaultListableBeanFactory factory = new DefaultListableBeanFactory();

        AnnotationAwareAspectJAutoProxyCreator proxyCreator = new AnnotationAwareAspectJAutoProxyCreator();
        proxyCreator.setBeanFactory(factory);
        factory.addBeanPostProcessor(proxyCreator);

        factory.registerBeanDefinition("myAspect" , BeanDefinitionBuilder
                .genericBeanDefinition(MyAspect.class)
                .getBeanDefinition());

        factory.registerBeanDefinition("bean1" , BeanDefinitionBuilder
                .genericBeanDefinition(Bean1.class)
                .getBeanDefinition());

        Bean1 bean1 = factory.getBean(Bean1.class);
        System.out.println("bean1 type -> " + bean1.getClass());
        bean1.foo();

        System.in.read();
    }


    @Aspect
    static class MyAspect {

        @Before("execution(* foo())")
        public void before() {
            System.out.println("@Aspect @Before ------------------------------");
        }

    }

    static class Bean1 {


        public Bean1() {
            System.out.println("======================== bean1 实例化 ");
        }

        public void foo() {
            System.out.println("======================== Bean1 foo ");
        }
    }
}

日志输出

======================== bean1 实例化 
21:16:30.709 [main] TRACE org.springframework.aop.aspectj.annotation.AnnotationAwareAspectJAutoProxyCreator - Creating implicit proxy for bean 'bean1' with 0 common interceptors and 2 specific interceptors
bean1 type -> class org.devx.spring.certified.professional.edu.hp.experiment.AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478
21:16:30.833 [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory - Creating shared instance of singleton bean 'myAspect'
@Aspect @Before ------------------------------
======================== Bean1 foo 

从日志中可以看到这是生成的代理对象类名 org.devx.spring.certified.professional.edu.hp.experiment.AopExp1$Bean1$EnhancerBySpringCGLIB$3f1c0478

CGLIB 生成代理对象源码

/*
 * Decompiled with CFR.
 */
package org.devx.spring.certified.professional.edu.hp.experiment;

import java.lang.reflect.Method;
import org.aopalliance.aop.Advice;
import org.devx.spring.certified.professional.edu.hp.experiment.AopExp1;
import org.springframework.aop.Advisor;
import org.springframework.aop.SpringProxy;
import org.springframework.aop.TargetClassAware;
import org.springframework.aop.TargetSource;
import org.springframework.aop.framework.Advised;
import org.springframework.aop.framework.AopConfigException;
import org.springframework.cglib.core.ReflectUtils;
import org.springframework.cglib.core.Signature;
import org.springframework.cglib.proxy.Callback;
import org.springframework.cglib.proxy.Dispatcher;
import org.springframework.cglib.proxy.Factory;
import org.springframework.cglib.proxy.MethodInterceptor;
import org.springframework.cglib.proxy.MethodProxy;
import org.springframework.cglib.proxy.NoOp;

public class AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478
extends AopExp1.Bean1
implements SpringProxy,
Advised,
Factory {
    private boolean CGLIB$BOUND;
    public static Object CGLIB$FACTORY_DATA;
    private static final ThreadLocal CGLIB$THREAD_CALLBACKS;
    private static final Callback[] CGLIB$STATIC_CALLBACKS;
    private MethodInterceptor CGLIB$CALLBACK_0;
    private MethodInterceptor CGLIB$CALLBACK_1;
    private NoOp CGLIB$CALLBACK_2;
    private Dispatcher CGLIB$CALLBACK_3;
    private Dispatcher CGLIB$CALLBACK_4;
    private MethodInterceptor CGLIB$CALLBACK_5;
    private MethodInterceptor CGLIB$CALLBACK_6;
    private static Object CGLIB$CALLBACK_FILTER;
    private static final Method CGLIB$foo$0$Method;
    private static final MethodProxy CGLIB$foo$0$Proxy;
    private static final Object[] CGLIB$emptyArgs;
    private static final Method CGLIB$equals$1$Method;
    private static final MethodProxy CGLIB$equals$1$Proxy;
    private static final Method CGLIB$toString$2$Method;
    private static final MethodProxy CGLIB$toString$2$Proxy;
    private static final Method CGLIB$hashCode$3$Method;
    private static final MethodProxy CGLIB$hashCode$3$Proxy;
    private static final Method CGLIB$clone$4$Method;
    private static final MethodProxy CGLIB$clone$4$Proxy;

    static void CGLIB$STATICHOOK1() {
        CGLIB$THREAD_CALLBACKS = new ThreadLocal();
        CGLIB$emptyArgs = new Object[0];
        Class<?> clazz = Class.forName("org.devx.spring.certified.professional.edu.hp.experiment.AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478");
        Class<?> clazz2 = Class.forName("java.lang.Object");
        Method[] methodArray = ReflectUtils.findMethods(new String[]{"equals", "(Ljava/lang/Object;)Z", "toString", "()Ljava/lang/String;", "hashCode", "()I", "clone", "()Ljava/lang/Object;"}, clazz2.getDeclaredMethods());
        CGLIB$equals$1$Method = methodArray[0];
        CGLIB$equals$1$Proxy = MethodProxy.create(clazz2, clazz, "(Ljava/lang/Object;)Z", "equals", "CGLIB$equals$1");
        CGLIB$toString$2$Method = methodArray[1];
        CGLIB$toString$2$Proxy = MethodProxy.create(clazz2, clazz, "()Ljava/lang/String;", "toString", "CGLIB$toString$2");
        CGLIB$hashCode$3$Method = methodArray[2];
        CGLIB$hashCode$3$Proxy = MethodProxy.create(clazz2, clazz, "()I", "hashCode", "CGLIB$hashCode$3");
        CGLIB$clone$4$Method = methodArray[3];
        CGLIB$clone$4$Proxy = MethodProxy.create(clazz2, clazz, "()Ljava/lang/Object;", "clone", "CGLIB$clone$4");
        clazz2 = Class.forName("org.devx.spring.certified.professional.edu.hp.experiment.AopExp1$Bean1");
        CGLIB$foo$0$Method = ReflectUtils.findMethods(new String[]{"foo", "()V"}, clazz2.getDeclaredMethods())[0];
        CGLIB$foo$0$Proxy = MethodProxy.create(clazz2, clazz, "()V", "foo", "CGLIB$foo$0");
    }

    final void CGLIB$foo$0() {
        super.foo();
    }

    @Override
    public final void foo() {
        MethodInterceptor methodInterceptor = this.CGLIB$CALLBACK_0;
        if (methodInterceptor == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            methodInterceptor = this.CGLIB$CALLBACK_0;
        }
        if (methodInterceptor != null) {
            Object object = methodInterceptor.intercept(this, CGLIB$foo$0$Method, CGLIB$emptyArgs, CGLIB$foo$0$Proxy);
            return;
        }
        super.foo();
    }

    final boolean CGLIB$equals$1(Object object) {
        return super.equals(object);
    }

    public final boolean equals(Object object) {
        MethodInterceptor methodInterceptor = this.CGLIB$CALLBACK_5;
        if (methodInterceptor == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            methodInterceptor = this.CGLIB$CALLBACK_5;
        }
        if (methodInterceptor != null) {
            Object object2 = methodInterceptor.intercept(this, CGLIB$equals$1$Method, new Object[]{object}, CGLIB$equals$1$Proxy);
            return object2 == null ? false : (Boolean)object2;
        }
        return super.equals(object);
    }

    final String CGLIB$toString$2() {
        return super.toString();
    }

    public final String toString() {
        MethodInterceptor methodInterceptor = this.CGLIB$CALLBACK_0;
        if (methodInterceptor == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            methodInterceptor = this.CGLIB$CALLBACK_0;
        }
        if (methodInterceptor != null) {
            return (String)methodInterceptor.intercept(this, CGLIB$toString$2$Method, CGLIB$emptyArgs, CGLIB$toString$2$Proxy);
        }
        return super.toString();
    }

    final int CGLIB$hashCode$3() {
        return super.hashCode();
    }

    public final int hashCode() {
        MethodInterceptor methodInterceptor = this.CGLIB$CALLBACK_6;
        if (methodInterceptor == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            methodInterceptor = this.CGLIB$CALLBACK_6;
        }
        if (methodInterceptor != null) {
            Object object = methodInterceptor.intercept(this, CGLIB$hashCode$3$Method, CGLIB$emptyArgs, CGLIB$hashCode$3$Proxy);
            return object == null ? 0 : ((Number)object).intValue();
        }
        return super.hashCode();
    }

    final Object CGLIB$clone$4() throws CloneNotSupportedException {
        return super.clone();
    }

    protected final Object clone() throws CloneNotSupportedException {
        MethodInterceptor methodInterceptor = this.CGLIB$CALLBACK_0;
        if (methodInterceptor == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            methodInterceptor = this.CGLIB$CALLBACK_0;
        }
        if (methodInterceptor != null) {
            return methodInterceptor.intercept(this, CGLIB$clone$4$Method, CGLIB$emptyArgs, CGLIB$clone$4$Proxy);
        }
        return super.clone();
    }

    public static MethodProxy CGLIB$findMethodProxy(Signature signature) {
        String string = ((Object)signature).toString();
        switch (string.hashCode()) {
            case -1268936465: {
                if (!string.equals("foo()V")) break;
                return CGLIB$foo$0$Proxy;
            }
            case -508378822: {
                if (!string.equals("clone()Ljava/lang/Object;")) break;
                return CGLIB$clone$4$Proxy;
            }
            case 1826985398: {
                if (!string.equals("equals(Ljava/lang/Object;)Z")) break;
                return CGLIB$equals$1$Proxy;
            }
            case 1913648695: {
                if (!string.equals("toString()Ljava/lang/String;")) break;
                return CGLIB$toString$2$Proxy;
            }
            case 1984935277: {
                if (!string.equals("hashCode()I")) break;
                return CGLIB$hashCode$3$Proxy;
            }
        }
        return null;
    }

    @Override
    public final int indexOf(Advisor advisor) {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        return ((Advised)dispatcher.loadObject()).indexOf(advisor);
    }

    @Override
    public final int indexOf(Advice advice) {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        return ((Advised)dispatcher.loadObject()).indexOf(advice);
    }

    @Override
    public final boolean isFrozen() {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        return ((Advised)dispatcher.loadObject()).isFrozen();
    }

    public final boolean isInterfaceProxied(Class clazz) {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        return ((Advised)dispatcher.loadObject()).isInterfaceProxied(clazz);
    }

    public final Class[] getProxiedInterfaces() {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        return ((Advised)dispatcher.loadObject()).getProxiedInterfaces();
    }

    @Override
    public final String toProxyConfigString() {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        return ((Advised)dispatcher.loadObject()).toProxyConfigString();
    }

    @Override
    public final boolean isProxyTargetClass() {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        return ((Advised)dispatcher.loadObject()).isProxyTargetClass();
    }

    @Override
    public final void setTargetSource(TargetSource targetSource) {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        ((Advised)dispatcher.loadObject()).setTargetSource(targetSource);
    }

    @Override
    public final TargetSource getTargetSource() {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        return ((Advised)dispatcher.loadObject()).getTargetSource();
    }

    @Override
    public final void setPreFiltered(boolean bl) {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        ((Advised)dispatcher.loadObject()).setPreFiltered(bl);
    }

    @Override
    public final boolean isExposeProxy() {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        return ((Advised)dispatcher.loadObject()).isExposeProxy();
    }

    @Override
    public final void setExposeProxy(boolean bl) {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        ((Advised)dispatcher.loadObject()).setExposeProxy(bl);
    }

    @Override
    public final Advisor[] getAdvisors() {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        return ((Advised)dispatcher.loadObject()).getAdvisors();
    }

    @Override
    public final int getAdvisorCount() {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        return ((Advised)dispatcher.loadObject()).getAdvisorCount();
    }

    @Override
    public final void addAdvisor(Advisor advisor) throws AopConfigException {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        ((Advised)dispatcher.loadObject()).addAdvisor(advisor);
    }

    @Override
    public final void addAdvisor(int n, Advisor advisor) throws AopConfigException {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        ((Advised)dispatcher.loadObject()).addAdvisor(n, advisor);
    }

    @Override
    public final boolean removeAdvice(Advice advice) {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        return ((Advised)dispatcher.loadObject()).removeAdvice(advice);
    }

    @Override
    public final void addAdvice(Advice advice) throws AopConfigException {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        ((Advised)dispatcher.loadObject()).addAdvice(advice);
    }

    @Override
    public final void addAdvice(int n, Advice advice) throws AopConfigException {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        ((Advised)dispatcher.loadObject()).addAdvice(n, advice);
    }

    @Override
    public final boolean removeAdvisor(Advisor advisor) {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        return ((Advised)dispatcher.loadObject()).removeAdvisor(advisor);
    }

    @Override
    public final void removeAdvisor(int n) throws AopConfigException {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        ((Advised)dispatcher.loadObject()).removeAdvisor(n);
    }

    @Override
    public final boolean replaceAdvisor(Advisor advisor, Advisor advisor2) throws AopConfigException {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        return ((Advised)dispatcher.loadObject()).replaceAdvisor(advisor, advisor2);
    }

    @Override
    public final boolean isPreFiltered() {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        return ((Advised)dispatcher.loadObject()).isPreFiltered();
    }

    public final Class getTargetClass() {
        Dispatcher dispatcher = this.CGLIB$CALLBACK_4;
        if (dispatcher == null) {
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
            dispatcher = this.CGLIB$CALLBACK_4;
        }
        return ((TargetClassAware)dispatcher.loadObject()).getTargetClass();
    }

    public AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478() {
        AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478 aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478 = this;
        AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478);
    }

    public static void CGLIB$SET_THREAD_CALLBACKS(Callback[] callbackArray) {
        CGLIB$THREAD_CALLBACKS.set(callbackArray);
    }

    public static void CGLIB$SET_STATIC_CALLBACKS(Callback[] callbackArray) {
        CGLIB$STATIC_CALLBACKS = callbackArray;
    }

    private static final void CGLIB$BIND_CALLBACKS(Object object) {
        block2: {
            Object object2;
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478 aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478;
            block3: {
                aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478 = (AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478)object;
                if (aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BOUND) break block2;
                aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BOUND = true;
                object2 = CGLIB$THREAD_CALLBACKS.get();
                if (object2 != null) break block3;
                object2 = CGLIB$STATIC_CALLBACKS;
                if (CGLIB$STATIC_CALLBACKS == null) break block2;
            }
            Callback[] callbackArray = (Callback[])object2;
            AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478 aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c04782 = aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478;
            aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c04782.CGLIB$CALLBACK_6 = (MethodInterceptor)callbackArray[6];
            aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c04782.CGLIB$CALLBACK_5 = (MethodInterceptor)callbackArray[5];
            aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c04782.CGLIB$CALLBACK_4 = (Dispatcher)callbackArray[4];
            aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c04782.CGLIB$CALLBACK_3 = (Dispatcher)callbackArray[3];
            aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c04782.CGLIB$CALLBACK_2 = (NoOp)callbackArray[2];
            aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c04782.CGLIB$CALLBACK_1 = (MethodInterceptor)callbackArray[1];
            aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c04782.CGLIB$CALLBACK_0 = (MethodInterceptor)callbackArray[0];
        }
    }

    @Override
    public Object newInstance(Callback[] callbackArray) {
        AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$SET_THREAD_CALLBACKS(callbackArray);
        AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478 aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478 = new AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478();
        AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$SET_THREAD_CALLBACKS(null);
        return aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478;
    }

    @Override
    public Object newInstance(Callback callback) {
        throw new IllegalStateException("More than one callback object required");
    }

    @Override
    public Object newInstance(Class[] classArray, Object[] objectArray, Callback[] callbackArray) {
        AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478 aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478;
        AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$SET_THREAD_CALLBACKS(callbackArray);
        Class[] classArray2 = classArray;
        switch (classArray.length) {
            case 0: {
                aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478 = new AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478();
                break;
            }
            default: {
                throw new IllegalArgumentException("Constructor not found");
            }
        }
        AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$SET_THREAD_CALLBACKS(null);
        return aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478;
    }

    @Override
    public Callback getCallback(int n) {
        Callback callback;
        AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
        AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478 aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478 = this;
        switch (n) {
            case 0: {
                callback = aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$CALLBACK_0;
                break;
            }
            case 1: {
                callback = aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$CALLBACK_1;
                break;
            }
            case 2: {
                callback = aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$CALLBACK_2;
                break;
            }
            case 3: {
                callback = aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$CALLBACK_3;
                break;
            }
            case 4: {
                callback = aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$CALLBACK_4;
                break;
            }
            case 5: {
                callback = aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$CALLBACK_5;
                break;
            }
            case 6: {
                callback = aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$CALLBACK_6;
                break;
            }
            default: {
                callback = null;
            }
        }
        return callback;
    }

    @Override
    public void setCallback(int n, Callback callback) {
        switch (n) {
            case 0: {
                this.CGLIB$CALLBACK_0 = (MethodInterceptor)callback;
                break;
            }
            case 1: {
                this.CGLIB$CALLBACK_1 = (MethodInterceptor)callback;
                break;
            }
            case 2: {
                this.CGLIB$CALLBACK_2 = (NoOp)callback;
                break;
            }
            case 3: {
                this.CGLIB$CALLBACK_3 = (Dispatcher)callback;
                break;
            }
            case 4: {
                this.CGLIB$CALLBACK_4 = (Dispatcher)callback;
                break;
            }
            case 5: {
                this.CGLIB$CALLBACK_5 = (MethodInterceptor)callback;
                break;
            }
            case 6: {
                this.CGLIB$CALLBACK_6 = (MethodInterceptor)callback;
                break;
            }
        }
    }

    @Override
    public Callback[] getCallbacks() {
        AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$BIND_CALLBACKS(this);
        AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478 aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478 = this;
        return new Callback[]{this.CGLIB$CALLBACK_0, this.CGLIB$CALLBACK_1, this.CGLIB$CALLBACK_2, this.CGLIB$CALLBACK_3, this.CGLIB$CALLBACK_4, this.CGLIB$CALLBACK_5, this.CGLIB$CALLBACK_6};
    }

    @Override
    public void setCallbacks(Callback[] callbackArray) {
        this.CGLIB$CALLBACK_0 = (MethodInterceptor)callbackArray[0];
        this.CGLIB$CALLBACK_1 = (MethodInterceptor)callbackArray[1];
        this.CGLIB$CALLBACK_2 = (NoOp)callbackArray[2];
        this.CGLIB$CALLBACK_3 = (Dispatcher)callbackArray[3];
        this.CGLIB$CALLBACK_4 = (Dispatcher)callbackArray[4];
        this.CGLIB$CALLBACK_5 = (MethodInterceptor)callbackArray[5];
        Callback[] callbackArray2 = callbackArray;
        AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478 aopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478 = this;
        this.CGLIB$CALLBACK_6 = (MethodInterceptor)callbackArray[6];
    }

    static {
        AopExp1$Bean1$$EnhancerBySpringCGLIB$$3f1c0478.CGLIB$STATICHOOK1();
    }
}

重点看 foo() 方法, 再调用了 MethodInterceptor 的 intercept 后会调用父类的 foo() 方法。

public final void foo() {
    MethodInterceptor methodInterceptor = this.CGLIB$CALLBACK_0;
    if (methodInterceptor == null) {
        AopExp1$Bean1$$EnhancerBySpringCGLIB$$5974b8b5.CGLIB$BIND_CALLBACKS(this);
        methodInterceptor = this.CGLIB$CALLBACK_0;
    }
    if (methodInterceptor != null) {
        Object object = methodInterceptor.intercept(this, CGLIB$foo$0$Method, CGLIB$emptyArgs, CGLIB$foo$0$Proxy);
        return;
    }
    super.foo();
}

再结合 spring 创建 CGLIB 代理时的代码来看 this.CGLIB$CALLBACK_0 对应的就是 DynamicAdvisedInterceptor 。

org.springframework.aop.framework.CglibAopProxy#getCallbacks

private Callback[] getCallbacks(Class<?> rootClass) throws Exception {
   // Parameters used for optimization choices...
   boolean exposeProxy = this.advised.isExposeProxy();
   boolean isFrozen = this.advised.isFrozen();
   boolean isStatic = this.advised.getTargetSource().isStatic();

   // Choose an "aop" interceptor (used for AOP calls).
   Callback aopInterceptor = new DynamicAdvisedInterceptor(this.advised);

   // Choose a "straight to target" interceptor. (used for calls that are
   // unadvised but can return this). May be required to expose the proxy.
   Callback targetInterceptor;
   if (exposeProxy) {
      targetInterceptor = (isStatic ?
            new StaticUnadvisedExposedInterceptor(this.advised.getTargetSource().getTarget()) :
            new DynamicUnadvisedExposedInterceptor(this.advised.getTargetSource()));
   }
   else {
      targetInterceptor = (isStatic ?
            new StaticUnadvisedInterceptor(this.advised.getTargetSource().getTarget()) :
            new DynamicUnadvisedInterceptor(this.advised.getTargetSource()));
   }

   // Choose a "direct to target" dispatcher (used for
   // unadvised calls to static targets that cannot return this).
   Callback targetDispatcher = (isStatic ?
         new StaticDispatcher(this.advised.getTargetSource().getTarget()) : new SerializableNoOp());

   Callback[] mainCallbacks = new Callback[] {
         aopInterceptor,  // for normal advice
         targetInterceptor,  // invoke target without considering advice, if optimized
         new SerializableNoOp(),  // no override for methods mapped to this
         targetDispatcher, this.advisedDispatcher,
         new EqualsInterceptor(this.advised),
         new HashCodeInterceptor(this.advised)
   };

   Callback[] callbacks;

   // If the target is a static one and the advice chain is frozen,
   // then we can make some optimizations by sending the AOP calls
   // direct to the target using the fixed chain for that method.
   if (isStatic && isFrozen) {
      Method[] methods = rootClass.getMethods();
      Callback[] fixedCallbacks = new Callback[methods.length];
      this.fixedInterceptorMap = CollectionUtils.newHashMap(methods.length);

      // TODO: small memory optimization here (can skip creation for methods with no advice)
      for (int x = 0; x < methods.length; x++) {
         Method method = methods[x];
         List<Object> chain = this.advised.getInterceptorsAndDynamicInterceptionAdvice(method, rootClass);
         fixedCallbacks[x] = new FixedChainStaticTargetInterceptor(
               chain, this.advised.getTargetSource().getTarget(), this.advised.getTargetClass());
         this.fixedInterceptorMap.put(method, x);
      }

      // Now copy both the callbacks from mainCallbacks
      // and fixedCallbacks into the callbacks array.
      callbacks = new Callback[mainCallbacks.length + fixedCallbacks.length];
      System.arraycopy(mainCallbacks, 0, callbacks, 0, mainCallbacks.length);
      System.arraycopy(fixedCallbacks, 0, callbacks, mainCallbacks.length, fixedCallbacks.length);
      this.fixedInterceptorOffset = mainCallbacks.length;
   }
   else {
      callbacks = mainCallbacks;
   }
   return callbacks;
}

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