做seo网站的公司,wordpress扫公众号二维码登录,广东网站建设定制,建筑英才招聘网首页书接上文#xff0c;上文说到#xff0c;specificInterceptors 不为空则执行createProxy方法创建代理对象#xff0c;即下图的createProxy方法开始执行#xff0c;生成代理对象#xff0c;生成代理对象有两种方式#xff0c;JDK和CGLIB。 createAopProxy就是决定使用哪…书接上文上文说到specificInterceptors 不为空则执行createProxy方法创建代理对象即下图的createProxy方法开始执行生成代理对象生成代理对象有两种方式JDK和CGLIB。 createAopProxy就是决定使用哪种方式生成动态代理对象方法执行流程和代码如下:
/*** 真正的创建代理判断一些列条件有自定义的接口的就会创建jdk代理否则就是cglib* param config the AOP configuration in the form of an* AdvisedSupport object* return* throws AopConfigException*/Overridepublic AopProxy createAopProxy(AdvisedSupport config) throws AopConfigException {// 这段代码用来判断选择哪种创建代理对象的方式// config.isOptimize() 是否对代理类的生成使用策略优化 其作用是和isProxyTargetClass是一样的 默认为false// config.isProxyTargetClass() 是否使用Cglib的方式创建代理对象 默认为false// hasNoUserSuppliedProxyInterfaces目标类是否有接口存在 且只有一个接口的时候接口类型不是SpringProxy类型if (config.isOptimize() || config.isProxyTargetClass() || hasNoUserSuppliedProxyInterfaces(config)) {// 上面的三个方法有一个为true的话则进入到这里// 从AdvisedSupport中获取目标类 类对象Class? targetClass config.getTargetClass();if (targetClass null) {throw new AopConfigException(TargetSource cannot determine target class: Either an interface or a target is required for proxy creation.);}// 判断目标类是否是接口 如果目标类是接口的话则还是使用JDK的方式生成代理对象// 如果目标类是Proxy类型 则还是使用JDK的方式生成代理对象if (targetClass.isInterface() || Proxy.isProxyClass(targetClass)) {return new JdkDynamicAopProxy(config);}// 配置了使用Cglib进行动态代理或者目标类没有接口,那么使用Cglib的方式创建代理对象return new ObjenesisCglibAopProxy(config);}else {// 使用JDK的提供的代理方式生成代理对象return new JdkDynamicAopProxy(config);}}
此处使用ObjenesisCglibAopProxy方式 getProxy:168, CglibAopProxy (org.springframework.aop.framework) 创建代理对象方法及注释如下:
/*** 获取cglib的代理对象* param classLoader the class loader to create the proxy with* (or {code null} for the low-level proxy facilitys default)* return*/Overridepublic Object getProxy(Nullable ClassLoader classLoader) {if (logger.isTraceEnabled()) {logger.trace(Creating CGLIB proxy: this.advised.getTargetSource());}try {// 从advised中获取ioc容器中配置的target对象Class? rootClass this.advised.getTargetClass();Assert.state(rootClass ! null, Target class must be available for creating a CGLIB proxy);Class? proxySuperClass rootClass;//如果目标对象已经是CGLIB 生成代理对象就是比较类名称中有 $$ 字符串那么就取目标对象的父类作为目标对象的类if (rootClass.getName().contains(ClassUtils.CGLIB_CLASS_SEPARATOR)) {proxySuperClass rootClass.getSuperclass();// 获取原始父类的接口Class?[] additionalInterfaces rootClass.getInterfaces();for (Class? additionalInterface : additionalInterfaces) {this.advised.addInterface(additionalInterface);}}// Validate the class, writing log messages as necessary.// 打印出不能代理的方法名CGLIB 是使用继承实现的所以final , static 的方法不能被增强validateClassIfNecessary(proxySuperClass, classLoader);// Configure CGLIB Enhancer...// 创建及配置EnhancerEnhancer enhancer createEnhancer();if (classLoader ! null) {enhancer.setClassLoader(classLoader);if (classLoader instanceof SmartClassLoader ((SmartClassLoader) classLoader).isClassReloadable(proxySuperClass)) {enhancer.setUseCache(false);}}// 配置超类代理类实现的接口回调方法等enhancer.setSuperclass(proxySuperClass);enhancer.setInterfaces(AopProxyUtils.completeProxiedInterfaces(this.advised));enhancer.setNamingPolicy(SpringNamingPolicy.INSTANCE);enhancer.setStrategy(new ClassLoaderAwareGeneratorStrategy(classLoader));// 获取callbacksCallback[] callbacks getCallbacks(rootClass);Class?[] types new Class?[callbacks.length];for (int x 0; x types.length; x) {types[x] callbacks[x].getClass();}// fixedInterceptorMap only populated at this point, after getCallbacks call aboveenhancer.setCallbackFilter(new ProxyCallbackFilter(this.advised.getConfigurationOnlyCopy(), this.fixedInterceptorMap, this.fixedInterceptorOffset));enhancer.setCallbackTypes(types);// Generate the proxy class and create a proxy instance.// 通过 Enhancer 生成代理对象并设置回调return createProxyClassAndInstance(enhancer, callbacks);}catch (CodeGenerationException | IllegalArgumentException ex) {throw new AopConfigException(Could not generate CGLIB subclass of this.advised.getTargetClass() : Common causes of this problem include using a final class or a non-visible class,ex);}catch (Throwable ex) {// TargetSource.getTarget() failedthrow new AopConfigException(Unexpected AOP exception, ex);}}rootClass是需要被代理的对象Enhancer该类用于生成代理对象代理如何生成:CGLIB和JDK两种生成方式。
getProxy:168, CglibAopProxy (org.springframework.aop.framework)
getProxy:116, ProxyFactory (org.springframework.aop.framework)
createProxy:519, AbstractAutoProxyCreator (org.springframework.aop.framework.autoproxy)
wrapIfNecessary:383, AbstractAutoProxyCreator (org.springframework.aop.framework.autoproxy)
postProcessAfterInitialization:319, AbstractAutoProxyCreator (org.springframework.aop.framework.autoproxy)
applyBeanPostProcessorsAfterInitialization:529, AbstractAutowireCapableBeanFactory (org.springframework.beans.factory.support)
initializeBean:2273, AbstractAutowireCapableBeanFactory (org.springframework.beans.factory.support)
doCreateBean:736, AbstractAutowireCapableBeanFactory (org.springframework.beans.factory.support)
createBean:630, AbstractAutowireCapableBeanFactory (org.springframework.beans.factory.support)
lambda$doGetBean$0:417, AbstractBeanFactory (org.springframework.beans.factory.support)
getObject:-1, 71399214 (org.springframework.beans.factory.support.AbstractBeanFactory$$Lambda$12)
getSingleton:370, DefaultSingletonBeanRegistry (org.springframework.beans.factory.support)
doGetBean:414, AbstractBeanFactory (org.springframework.beans.factory.support)
getBean:260, AbstractBeanFactory (org.springframework.beans.factory.support)
preInstantiateSingletons:993, DefaultListableBeanFactory (org.springframework.beans.factory.support)
finishBeanFactoryInitialization:1024, AbstractApplicationContext (org.springframework.context.support)
refresh:614, AbstractApplicationContext (org.springframework.context.support)
init:150, ClassPathXmlApplicationContext (org.springframework.context.support)
init:87, ClassPathXmlApplicationContext (org.springframework.context.support)
main:15, TestAop (com.mashibing.aop.xml)一级缓存里是MyCalculator的代理对象 后续执行就是这个代理对象的方法然后跳转到 intercept:709, CglibAopProxy$DynamicAdvisedInterceptor (org.springframework.aop.framework) 这个方法 OverrideNullablepublic Object intercept(Object proxy, Method method, Object[] args, MethodProxy methodProxy) throws Throwable {Object oldProxy null;boolean setProxyContext false;Object target null;TargetSource targetSource this.advised.getTargetSource();try {if (this.advised.exposeProxy) {// Make invocation available if necessary.oldProxy AopContext.setCurrentProxy(proxy);setProxyContext true;}// Get as late as possible to minimize the time we own the target, in case it comes from a pool...target targetSource.getTarget();Class? targetClass (target ! null ? target.getClass() : null);// 从advised中获取配置好的AOP通知ListObject chain this.advised.getInterceptorsAndDynamicInterceptionAdvice(method, targetClass);Object retVal;// Check whether we only have one InvokerInterceptor: that is,// no real advice, but just reflective invocation of the target.// 如果没有aop通知配置那么直接调用target对象的调用方法if (chain.isEmpty() Modifier.isPublic(method.getModifiers())) {// We can skip creating a MethodInvocation: just invoke the target directly.// Note that the final invoker must be an InvokerInterceptor, so we know// it does nothing but a reflective operation on the target, and no hot// swapping or fancy proxying.Object[] argsToUse AopProxyUtils.adaptArgumentsIfNecessary(method, args);// 如果拦截器链为空则直接激活原方法retVal methodProxy.invoke(target, argsToUse);}else {// We need to create a method invocation...// 通过cglibMethodInvocation来启动advice通知retVal new CglibMethodInvocation(proxy, target, method, args, targetClass, chain, methodProxy).proceed();}retVal processReturnType(proxy, target, method, retVal);return retVal;}finally {if (target ! null !targetSource.isStatic()) {targetSource.releaseTarget(target);}if (setProxyContext) {// Restore old proxy.AopContext.setCurrentProxy(oldProxy);}}}Overridepublic boolean equals(Nullable Object other) {return (this other ||(other instanceof DynamicAdvisedInterceptor this.advised.equals(((DynamicAdvisedInterceptor) other).advised)));} chain {ArrayList2276} size 6 0 {ExposeInvocationInterceptor2242} 1 {AspectJAfterThrowingAdvice2282} “org.springframework.aop.aspectj.AspectJAfterThrowingAdvice: advice method [public static void com.mashibing.aop.xml.util.LogUtil.logException(org.aspectj.lang.JoinPoint,java.lang.Exception)]; aspect name ‘logUtil’” 2 {AfterReturningAdviceInterceptor2283} 3 {AspectJAfterAdvice2284} “org.springframework.aop.aspectj.AspectJAfterAdvice: advice method [public static void com.mashibing.aop.xml.util.LogUtil.logFinally(org.aspectj.lang.JoinPoint)]; aspect name ‘logUtil’” 4 {AspectJAroundAdvice2285} “org.springframework.aop.aspectj.AspectJAroundAdvice: advice method [public java.lang.Object com.mashibing.aop.xml.util.LogUtil.around(org.aspectj.lang.ProceedingJoinPoint) throws java.lang.Throwable]; aspect name ‘logUtil’” 5 {MethodBeforeAdviceInterceptor2286} 执行的就是上面6个的通知通过索引下标挨个执行
retVal new CglibMethodInvocation(proxy, target, method, args, targetClass, chain, methodProxy).proceed();执行顺序如下: 本文主要讲解springAop如何创建动态代理对象以及使用哪种方式创建的依据在执行方法跳转到生成的代理对象中然后生成拦截器链去执行
