springframework【8】

Spring的Advices
Advices实现了Aspect的真正逻辑。由于织入至Targets的实际不同，spring提供了不同的Advices，像Before Advice，After Advice，Around Advice，Throw Advice。
（1）、Before Advice
通过实现MethodBeforeAdvice来定义
（2）、After Advice
通过实现AfterReturningAdvice来定义
（3）、Around Advice
通过实现MethodInterceptor来定义
（4）、Throw Advice
通过实现ThrowsAdvice来定义

我们将使用一个代理的bean aaa，给这个代理的bean加上我们spring的advice，看看他的日志输出表现。我们通过代码示例来说明：

1、定义基本的advice Bean以及要被调用的类

（1）、beforeAdvice的Bean

 

package com.itcast.advice;

import java.lang.reflect.Method;

import org.springframework.aop.MethodBeforeAdvice;

/**
 * 调用方法之前
 * */
public class LogBeforeAdvice implements MethodBeforeAdvice {
	public void before(Method method, Object[] args, Object target)
			throws Throwable {
		System.out.println("beforeAdvice 调用方法之前被执行！...........");
	}
}

 

（2）、afterAdvice的bean

 

package com.itcast.advice;

import java.lang.reflect.Method;
import org.springframework.aop.AfterReturningAdvice;

public class LogAfterAdvice implements AfterReturningAdvice {
	public void afterReturning(Object returnValue, Method method,
			Object[] args, Object target) throws Throwable {
		System.out.println("afterAdvice 调用方法之后被执行！...........");
	}
}

 

（3）、Around advice的Bean

package com.itcast.advice;

import org.aopalliance.intercept.MethodInterceptor;
import org.aopalliance.intercept.MethodInvocation;

/**
 * 环绕通知
 * */
public class LogAroundAdvice implements MethodInterceptor {

	public Object invoke(MethodInvocation mi) throws Throwable {
		Object result=null;
		System.out.println("around 调用方法之前....");
		
		result=mi.proceed();
		
		System.out.println("around 调用方法之后...");
		return result;
	}
}

 

（4）、Throw Advice的Bean

package com.itcast.advice;

import java.lang.reflect.Method;


import org.springframework.aop.ThrowsAdvice;

/**抛出异常时候的通知*/
public class ThrowAdvice implements ThrowsAdvice {

    public void afterThrowing(Method method,Object[] args,Object target,Throwable subclass) {
    	System.out.println("ThrowAdvice 记录异常...........");
    }

}

 

（5）、要被代理的类

package com.itcast.proxy;

public class HelloSpeaker1 implements IHello {

	public void hi() {
		System.out.println("我在HelloSpeaker1中");
	}
	public void hiAAA(String aaa) {
		System.out.println("我在HelloSpeaker1中---hiAAA["+aaa+"]");
	}

	public void hiBBB(String bbb) throws Exception {
		System.out.println("我在HelloSpeaker1中---hiBBB["+bbb+"]");
		throw new Exception("aaa");
	}
}

package com.itcast.proxy;

/**
 * 代理接口
 * */
public interface IHello {
	
	public void hi();
	
	public void hiAAA(String aaa);
	
	public void hiBBB(String bbb) throws Exception;

}

 

2、在配置文件中声明我们的bean

<!-- 代理 -->
<bean id="helloSpeaker1" class="com.itcast.proxy.HelloSpeaker1"></bean>

<!-- 声明四种通知类型,其实就是你想加入到其他被代理程序执行逻辑中的代码 -->
<bean id="beforeAdvice" class="com.itcast.advice.LogBeforeAdvice"/>
<bean id="afterAdvice" class="com.itcast.advice.LogAfterAdvice"></bean>
<bean id="aroundAdvice" class="com.itcast.advice.LogAroundAdvice"></bean>
<bean id="throwAdvice" class="com.itcast.advice.ThrowAdvice"></bean>
<!-- 基础的通知使用，这里强行给helloSpeaker1加上了advice通知 -->
<bean id="aaa" class="org.springframework.aop.framework.ProxyFactoryBean">
  <property name="target" ref="helloSpeaker1"></property>
  <property name="interceptorNames">
  <list>
    <value>aroundAdvice</value>
    <value>beforeAdvice</value>
    <value>afterAdvice</value>
    <value>throwAdvice</value>
  </list>
  </property>
</bean>

 

3、在main函数中调用

package com.itcast.advice;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.itcast.proxy.IHello;

public class AdviceMain {
/**对于给基本的spring bean强行指定一批advice方法的调用展示**/
	public static void main(String[] args) {
		ApplicationContext ctx = new ClassPathXmlApplicationContext("bean-config.xml");
		IHello h = (IHello)ctx.getBean("aaa");
		h.hiAAA("测试配置aop的adivce");
		
		System.out.println("进行抛出异常的adivce展示-==================");
		try {
			h.hiBBB("测试抛出异常的advice");
		} catch (Exception e) {
		}
	}

}

 

4、控制台的显示

around 调用方法之前....
beforeAdvice 调用方法之前被执行！...........
我在HelloSpeaker1中---hiAAA[测试配置aop的adivce]
afterAdvice 调用方法之后被执行！...........
around 调用方法之后...
进行抛出异常的adivce展示-==================
15:05:05,671 DEBUG ThrowsAdviceInterceptor:88 - Found exception handler method: public void com.itcast.advice.ThrowAdvice.afterThrowing(java.lang.reflect.Method,java.lang.Object[],java.lang.Object,java.lang.Throwable)
around 调用方法之前....
beforeAdvice 调用方法之前被执行！...........
我在HelloSpeaker1中---hiBBB[测试抛出异常的advice]
15:05:05,687 DEBUG ThrowsAdviceInterceptor:119 - Found handler for exception of type [java.lang.Throwable]: public void com.itcast.advice.ThrowAdvice.afterThrowing(java.lang.reflect.Method,java.lang.Object[],java.lang.Object,java.lang.Throwable)
ThrowAdvice 记录异常...........