AspectJ的注解开发AOP：环绕通知的学习

环绕通知的注解为@Around
around方法的返回值就是目标代理方法执行返回值
参数ProceedingJoinPoint可以拦截目标方法的执行
切面类配置如下
i

mport org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.AfterReturning;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;

import java.math.BigInteger;

@Aspect
public class aspectj {
// @Before(value = "execution(* com.AspecJ.xiaomaoDao.*(..))")
// public void before(){
// System.out.println("我是前置通知！");
// }


// @AfterReturning(value = "execution(* com.AspecJ.xiaomaoDao.delete())",returning = "element")
// 使用returning来接受返回值
// public void After(Object element){
// System.out.println("我删除了"+element); //打印输出了返回值
// }

@Around(value="execution(* com.AspecJ.xiaomaoDao.update())")
public Object around(ProceedingJoinPoint joinPoint){
Object obj=null;
System.out.println("环绕前");
try {
obj=joinPoint.proceed();
} catch (Throwable throwable) {
throwable.printStackTrace();
}
System.out.println("环绕后");
return obj;
}
}

目标类方法如下：

public class xiaomaoDao {
public void save(){
System.out.println("save xiaomao!");
}
public void find(){
System.out.println("find xiaomao!");
}
public String delete(){
System.out.println("delete xiaomao!");
return "xiaomao";
}
public void update(){
System.out.println("update xiaomao!");
}
}

执行结果如下：

delete xiaomao!
find xiaomao!
save xiaomao!
环绕前
update xiaomao!
环绕后