首先看一下基于注解的切面类，这时的切面不仅仅是一个POJO类了，与AOP进行了紧密的耦合。但是配置过程和方式都与原来的方式差不多。
package com.spring.test.chap44; import org.aspectj.lang.annotation.AfterReturning;
import org.aspectj.lang.annotation.AfterThrowing;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.springframework.stereotype.Component;
@Component
@Aspect
public class Audience {
@Pointcut("execution(* com.spring.test.chap44.Instrumentalist.perform(..))")
public void performance(){} @Before("performance()")
public void takeSeats(){
System.out.println("takeSeats()");
}
@Before("performance()")
public void turnOffCellphones(){
System.out.println("turnOffCellphones()");
}
@AfterReturning("performance()")
public void applaud(){
System.out.println("applaud()");
}
@AfterThrowing("performance()")
public void demandRefund(){
System.out.println("demandRefund()");
}
}
接下来是其他一些必不可少的类：
切点接口类：
package com.spring.test.chap44;
public interface Performer {
public void perform();
}切点实现类：
package com.spring.test.chap44; import org.springframework.stereotype.Component; @Component
public class Instrumentalist implements Performer{
public void perform() {
System.out.println("__________ perform ___________");
}
}
测试类：
package com.spring.test.chap44; import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext; public class test {
public static void main(String[] args) {
ApplicationContext ctx = new ClassPathXmlApplicationContext("bean.xml"); Performer performer = (Performer)ctx.getBean("xingoo");
performer.perform();
}
}
下面是重点的配置文件
此时的配置文件注意要使spring知道哪一个是普通的bean，哪一个是通知。因此需要加上一个属性，保证AOP自动的识别通知。
<aop:aspectj-autoproxy proxy-target-class="true"/>
配置文件如下:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-3.0.xsd">
<bean id="xingoo" class="com.spring.test.chap44.Instrumentalist"/>
<bean id="audience" class="com.spring.test.chap44.Audience" />
<aop:aspectj-autoproxy proxy-target-class="true"/>
</beans>
执行结果如下：
turnOffCellphones()
takeSeats()
__________ perform ___________
applaud()
如果需要使用around只需要在切面中添加如下的代码就可以了：
@Around("performance()")
public void watchPerformance(ProceedingJoinPoint joinpoint){
try{
System.out.println("");
long start = System.currentTimeMillis();
joinpoint.proceed();
long end = System.currentTimeMillis();
System.out.println("time—— "+(end-start)+" millinseconds");
System.out.println("");
}catch(Throwable t){
System.out.println("in watchPerformance Throwable()");
}
}对于参数的传递的通知，也与原先通过配置的差不多
在切面中配置好切点的方法，注意带上参数
private String str;
@Pointcut("execution(* com.spring.test.chap44.Instrumentalist.perform(String)) && args(str)")
public void performance(String str){} @Before("performance(str)")
public void takeSeats(String str){
System.out.println("takeSeats()"+str);
}
其他的基本都不用动了，只要把切点的方法，修改成带有参数的就可以了
public class Instrumentalist implements Performer{
public void perform(String str) {
System.out.println("__________ perform ___________" + str);
}
}