标签：after ons 执行 invoke boolean under param out ted
MethodInterceptor AdvisorAdapter和Advice之间实现了适配器模式
首先增加方法的执行时通过拦截器链进行执行的，而配置文件配置的参数解析完以后是一增强对象的形式进行封装的
拦截器要想调用增强Advice的增强方法，是无法直接方访问的，因此加一个增强适配类，将增强转换为拦截器
MethodInterceptor的结构：
public interface MethodInterceptor extends Interceptor { /** * Implement this method to perform extra treatments before and * after the invocation. Polite implementations would certainly * like to invoke {@link Joinpoint#proceed()}. * * @param invocation the method invocation joinpoint * @return the result of the call to {@link * Joinpoint#proceed()}, might be intercepted by the * interceptor. * * @throws Throwable if the interceptors or the * target-object throws an exception. */ Object invoke(MethodInvocation invocation) throws Throwable; }
Advice结构：
/** * Tag interface for Advice. Implementations can be any type * of advice, such as Interceptors. * @author Rod Johnson * @version $Id: Advice.java,v 1.1 2004/03/19 17:02:16 johnsonr Exp $ */ public interface Advice { }
AdvisorAdapter结构可以看到AdvisorAdapter中提供了对增强Advice的访问方式和转换方法
public interface AdvisorAdapter { /** * Does this adapter understand this advice object? Is it valid to * invoke the {@code getInterceptors} method with an Advisor that * contains this advice as an argument? * @param advice an Advice such as a BeforeAdvice * @return whether this adapter understands the given advice object * @see #getInterceptor(org.springframework.aop.Advisor) * @see org.springframework.aop.BeforeAdvice */ boolean supportsAdvice(Advice advice); /** * Return an AOP Alliance MethodInterceptor exposing the behavior of * the given advice to an interception-based AOP framework. * <p>Don‘t worry about any Pointcut contained in the Advisor; * the AOP framework will take care of checking the pointcut. * @param advisor the Advisor. The supportsAdvice() method must have * returned true on this object * @return an AOP Alliance interceptor for this Advisor. There‘s * no need to cache instances for efficiency, as the AOP framework * caches advice chains. */ MethodInterceptor getInterceptor(Advisor advisor); }
因为有三种增强
after 对应 AfterReturningAdviceAdapter
before 对应MethodBeforeAdviceAdapter
在他们的getInterceptor的方法里面实现了将advice转换为拦截器的方法
@SuppressWarnings("serial")
class MethodBeforeAdviceAdapter implements AdvisorAdapter, Serializable {
@Override
public boolean supportsAdvice(Advice advice) {
return (advice instanceof MethodBeforeAdvice);
}
@Override
public MethodInterceptor getInterceptor(Advisor advisor) {
MethodBeforeAdvice advice = (MethodBeforeAdvice) advisor.getAdvice();
return new MethodBeforeAdviceInterceptor(advice);
}
}
@SuppressWarnings("serial")
class AfterReturningAdviceAdapter implements AdvisorAdapter, Serializable {
@Override
public boolean supportsAdvice(Advice advice) {
return (advice instanceof AfterReturningAdvice);
}
@Override
public MethodInterceptor getInterceptor(Advisor advisor) {
AfterReturningAdvice advice = (AfterReturningAdvice) advisor.getAdvice();
return new AfterReturningAdviceInterceptor(advice);
}
}
标签：after ons 执行 invoke boolean under param out ted
原文地址：https://www.cnblogs.com/histlyb/p/9486233.html
