Springboot借助AOP简化自定义注解

0.前言

　　开发中经常会遇到处理重复的逻辑,如果每次都要去重复实现,则开发效率很低,因此可以去同一处理,比较常用的方式有拦截器,过滤器,aop等等,这里介绍通过自定义注解来处理,这样的优点是可以很好的控制粒度,示例为通过自定义注解统计请求的耗时.

1.maven依赖

1 <dependency>
2     <groupId>org.springframework.boot</groupId>
3     <artifactId>spring-boot-starter-aop</artifactId>
4     <version>1.5.9.RELEASE</version>
5 </dependency>

2.自定义注解

 1 import java.lang.annotation.ElementType;
 2 import java.lang.annotation.Retention;
 3 import java.lang.annotation.RetentionPolicy;
 4 import java.lang.annotation.Target;
 5 
 6 @Target(ElementType.METHOD)
 7 @Retention(RetentionPolicy.RUNTIME)
 8 public @interface MyAnnotation {
 9     String note() default "";
10 }

3.AOP

 1 import org.aspectj.lang.JoinPoint;
 2 import org.aspectj.lang.annotation.After;
 3 import org.aspectj.lang.annotation.Aspect;
 4 import org.aspectj.lang.annotation.Before;
 5 import org.aspectj.lang.annotation.Pointcut;
 6 import org.springframework.stereotype.Component;
 7 
 8 @Aspect
 9 @Component
10 public class LogMethodCostTimeAspect {
11 
12     ThreadLocal<Long> beginTime = new ThreadLocal<>();
13 
14     @Pointcut("@annotation(myAnnotation)")
15     public void myPointcut(MyAnnotation myAnnotation) {
16     }
17 
18     @Before("myPointcut(myAnnotation)")
19     public void doBefore(JoinPoint joinPoint, MyAnnotation myAnnotation) {
20         System.err.println("方法执行开始");
21         //记录请求到达时间
22         beginTime.set(System.currentTimeMillis());
23          
24     }
25 
26     @After("myPointcut(myAnnotation)")
27     public void doAfter(MyAnnotation myAnnotation) {
28         System.err.println(myAnnotation.note() + (System.currentTimeMillis() - beginTime.get()) + " ms");
29         System.err.println("方法执行结束");
30     }
31 
32 }

4.Service实现

 1 @Service("demoService")
 2 public class DemoServiceImpl implements DemoService{
 3 
 4     @Override
 5     @MyAnnotation(note = "执行 demo 方法耗时")
 6     public void doSth() {
 7         for (int i = 0; i < 100; i++) {
 8             System.out.println("do something ...");
 9         }
10     }
11 }

5.Controller

 1 @Controller
 2 public class HelloController {
 3 
 4     @Autowired
 5     private DemoService demoService;
 6 
 7     @RequestMapping(value = "/hello")
 8     @ResponseBody
 9     public void getTime() {
10         demoService.doSth();
11     }
12 }

 

posted @ 2018-11-26 13:38  凛冬雪夜  阅读(271)  评论(0)    收藏  举报