# Springboot整合AOP和注解,实现丰富的切面功能

# 简介

我们在文章《Spring AOP与AspectJ的对比及应用 (opens new window)》介绍了AOP的使用,这篇文章讲解一下AOP与注解的整合,通过注解来使用AOP,会非常方便。为了简便,我们还是来实现一个计时的功能。

# 整合过程

首先创建一个注解:

@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface PkslowLogTime {
}

然后在一个Service中使用注解:

@Service
@Slf4j
public class TestService {
    @PkslowLogTime
    public void fetchData() {
        log.info("fetchData");
        try {
            Thread.sleep(500);
        } catch (InterruptedException e) {
            throw new RuntimeException(e);
        }
    }
}

这个Service的方法会在Controller中调用:

@GetMapping("/hello")
public String hello() {
  log.info("------hello() start---");
  test();
  staticTest();
  testService.fetchData();
  log.info("------hello() end---");
  return "Hello, pkslow.";
}

接着是关键一步,我们要实现切面,来找到注解并实现对应功能:

@Aspect
@Component
@Slf4j
public class PkslowLogTimeAspect {
    @Around("@annotation(com.pkslow.springboot.aop.PkslowLogTime) && execution(* *(..))")
    public Object doAround(ProceedingJoinPoint joinPoint) throws Throwable {
        log.info("------PkslowLogTime doAround start------");
        MethodSignature methodSignature = (MethodSignature) joinPoint.getSignature();

        // Get intercepted method details
        String className = methodSignature.getDeclaringType().getSimpleName();
        String methodName = methodSignature.getName();

        // Measure method execution time
        StopWatch stopWatch = new StopWatch(className + "->" + methodName);
        stopWatch.start(methodName);
        Object result = joinPoint.proceed();
        stopWatch.stop();
        // Log method execution time
        log.info(stopWatch.prettyPrint());
        log.info("------PkslowLogTime doAround end------");
        return result;
    }
}

@Around("@annotation(com.pkslow.springboot.aop.PkslowLogTime) && execution(* *(..))")这个表达式很关键,如果不对,将无法正确识别;还有可能出现多次调用的情况。多次调用的情况可以参考:Stackoverflow (opens new window)

这里使用了Spring的StopWatch来计时。

# 测试

通过maven build包:

$ mvn clean package

日志可以看到有对应的织入信息:

[INFO] Join point 'method-execution(java.lang.String com.pkslow.springboot.controller.TestController.hello())' in Type 'com.pkslow.springboot.controller.TestController' (TestController.java:22) advised by around advice from 'com.pkslow.springboot.aop.ControllerAspect' (ControllerAspect.class(from ControllerAspect.java))
[INFO] Join point 'method-execution(java.lang.String com.pkslow.springboot.controller.TestController.hello())' in Type 'com.pkslow.springboot.controller.TestController' (TestController.java:22) advised by before advice from 'com.pkslow.springboot.aop.ControllerAspect' (ControllerAspect.class(from ControllerAspect.java))
[INFO] Join point 'method-execution(void com.pkslow.springboot.controller.TestController.test())' in Type 'com.pkslow.springboot.controller.TestController' (TestController.java:31) advised by around advice from 'com.pkslow.springboot.aop.ControllerAspect' (ControllerAspect.class(from ControllerAspect.java))
[INFO] Join point 'method-execution(void com.pkslow.springboot.controller.TestController.test())' in Type 'com.pkslow.springboot.controller.TestController' (TestController.java:31) advised by before advice from 'com.pkslow.springboot.aop.ControllerAspect' (ControllerAspect.class(from ControllerAspect.java))
[INFO] Join point 'method-execution(void com.pkslow.springboot.controller.TestController.staticTest())' in Type 'com.pkslow.springboot.controller.TestController' (TestController.java:37) advised by around advice from 'com.pkslow.springboot.aop.ControllerAspect' (ControllerAspect.class(from ControllerAspect.java))
[INFO] Join point 'method-execution(void com.pkslow.springboot.controller.TestController.staticTest())' in Type 'com.pkslow.springboot.controller.TestController' (TestController.java:37) advised by before advice from 'com.pkslow.springboot.aop.ControllerAspect' (ControllerAspect.class(from ControllerAspect.java))
[INFO] Join point 'method-execution(void com.pkslow.springboot.service.TestService.fetchData())' in Type 'com.pkslow.springboot.service.TestService' (TestService.java:12) advised by around advice from 'com.pkslow.springboot.aop.PkslowLogTimeAspect' (PkslowLogTimeAspect.class(from PkslowLogTimeAspect.java))

启动应用后访问接口,日志如下:

# 总结

通过注解可以实现很多功能,也非常方便。而且注解还可以添加参数,组合使用更完美了。

代码请看GitHub: https://github.com/LarryDpk/pkslow-samples


References:

Log the method execution time using AOP for a spring boot application (opens new window)

上次更新: 2023/8/18 23:39:36