开启注解扫描
<context:component-scan base-package="aopSpring"></context:component-scan>
将AOP的注解应用到容器中
<aop:aspectj-autoproxy></aop:aspectj-autoproxy>
把横切关注点的代码添加到切面类中
@component
@Aspect
应用如下
aop/ArithMath
import org.springframework.stereotype.Component;
@Component
public class ArithMath {
public ArithMath(){}
public int add(int i,int j){
return i + j;
}
public int div(int i,int j){
return i / j;
}
}
在ArithMath方法执行过程中插入日志
编写切面类aop/ArithMathAopImp
@Component
@Aspect
public class ArithMathAopImp {
//前置增强@Before
@Before("execution(* aopSpring.ArithMath.add(int,int))")
public void loggingArithMath(JoinPoint joinPoint){ //添加参数JoinPoint 可以获取目标的参数
String methd = joinPoint.getSignature().getName();
List<Object> list = Arrays.asList(joinPoint.getArgs());
System.out.println("the mathod "+ methd +" on load begin whih "+list);
}
//后置增强不可访问方法返回值
@After(value="execution(* aopSpring.ArithMath.add(int,int))")
public void AfterMethod(JoinPoint joinPoint){
String method = joinPoint.getSignature().getName();
System.out.println("the mathod "+ method +" on end!");
}
//返回通知
@AfterReturning(value="execution(* aopSpring.ArithMath.add(int,int))",returning="rt")
public void AfterReturn(JoinPoint joinPoint,Object rt){
String method = joinPoint.getSignature().getName();
System.out.println("the mathod "+ method +" return "+rt);
}
//异常通知,
@AfterThrowing(value="execution(* aopSpring.ArithMath.*(int,int))",throwing="ex")
public void AfterThrowingMethod(JoinPoint joinPoint,Exception ex){ //指定特定的异常(Exception )发生时才执行代码
String method = joinPoint.getSignature().getName();
System.out.println("the mathod "+ method +" throw "+ex);
}
/**
* 环绕通知@Around
* 通知必须加参数ProceedingJoinPoint,且必须有返回值
* proceed()表示执行目标方法
*/
@Around("execution(* aopSpring.ArithMath.*(int,int))")
public Object AroundMethed(ProceedingJoinPoint pj){
Object rt = null;
String method = pj.getSignature().getName();
try {
//前置
System.out.println(method + "before");
rt = pj.proceed();
//后置
System.out.println(method + "after");
} catch (Throwable e) {
// TODO Auto-generated catch block
e.printStackTrace();
System.out.println(method + e);
}
//后置
System.out.println(method + "returnning");
return rt;
}