Spring中AOP注解@Aspect的使用详解

@Aspect
@Component
//设置注解执行的顺序
@Order(2)
public class AnnotationAspectTest 

/**
 * 定义切点,切点为对应controller
 */
@Pointcut("execution(public * com.example.zcs.Aop.controller.*.*(..))")
public void aopPointCut(){
}

@Controller
@RequestMapping("aop")
public class AopController {
    @RequestMapping("test")
    @ResponseBody
    public String aopTest(User user) {
       // System.out.println(user);
        System.out.println("aop测试");
        return "success";
    }
    @TestAnnotation(flag = false)
    @RequestMapping("aopAnnotationTest")
    @ResponseBody
    public String aopAnnotationTest(User user) {
        // System.out.println(user);
        System.out.println("aopAnnotationTest");
        return "success";
    }
}

@Aspect
@Component
//设置注解执行的顺序
@Order(1)
public class AspectTest {
    /**
     * 定义切点,切点为对应controller
     */
    @Pointcut("execution(public * com.example.zcs.Aop.controller.*.*(..))")
    public void aopPointCut(){
    }
    @Before("aopPointCut()")
    public void testbefor(JoinPoint joinPoint) {
        illegalParam(joinPoint);
        System.out.println("执行方法之前执行。。。。。");
    }
    @After("aopPointCut()")
    public void testAfter(JoinPoint joinPoint) {
        //illegalParam(joinPoint);
        System.out.println("执行方法之后执行。。。。。");
    }
    /**
     *获取请求参数
     * @param joinPoint
     * @return
     */
    private static void  illegalParam(JoinPoint joinPoint) {
        if(joinPoint == null){
            return;
        }
        boolean flag = false;
        try{
            // 参数值
            Object[] args = joinPoint.getArgs();
            if (args != null) {
                for (Object o : args) {
                    System.out.println(o);
                }
            }
        }catch(Exception e){
        }
    }
}

@Aspect
@Component
//设置注解执行的顺序
@Order(2)
public class AnnotationAspectTest {
    /**
     * 定义切点,切点为添加了注解的方法
     */
    @Pointcut("@annotation(com.example.zcs.Aop.annotation.TestAnnotation)")
    public void aopPointCut(){
    }
    @Around("aopPointCut()")
    public Object Around(ProceedingJoinPoint point) throws Throwable {
        System.out.println("AnnotationAspectTest Around start ");
        //获取注解和注解的值
        TestAnnotation annotation = getAnnotation(point);
       if (annotation != null) {
           boolean flag = annotation.flag();
           System.out.println("注解flags的值:" + flag);
       }
        //获取参数
        Object[] args = point.getArgs();
        for (Object arg : args) {
            System.out.println("arg ==>" + arg);
        }
        //去调用被拦截的方法
        Object proceed = point.proceed();
        return proceed;
    }
    //获取注解
    public TestAnnotation getAnnotation(ProceedingJoinPoint point) {
        Signature signature = point.getSignature();
        MethodSignature methodSignature = (MethodSignature) signature;
        Method method = methodSignature.getMethod();
        if (method != null){
            return method.getAnnotation(TestAnnotation.class);
        }
        return null;
    }
}

@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface TestAnnotation {
    boolean flag() default true;
}