AOP
AOP为Aspect Oriented Programming的缩写，意为：面向切面编程，通过预编译方式和运行期动态代理实现程序功能的统一维护的一种技术。在日常开发当中经常用来记录日志，方法跟踪、事务，权限等
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-aop</artifactId>
</dependency>@Aspect
@Component
@Slf4j
public class TestAspect {
//com.kzj.kzj_rabbitmq.controller 包中所有的类的所有方法切面
//@Pointcut("execution(public com.kzj.kzj_rabbitmq.controller..(..))")
//只针对 MessageController 类切面
//@Pointcut("execution(public com.kzj.kzj_rabbitmq.controller.MessageController.(..))")
//统一切点,对com.kzj.kzj_rabbitmq.controller及其子包中所有的类的所有方法切面
@Pointcut("execution(public com.kzj.kzj_rabbitmq.controller...(..))")
public void Pointcut() {
}
//前置通知
@Before("Pointcut()")
public void beforeMethod(JoinPoint joinPoint){
log.info("调用了前置通知");
}
//@After: 后置通知
@After("Pointcut()")
public void afterMethod(JoinPoint joinPoint){
log.info("调用了后置通知");
}
//@AfterRunning: 返回通知 rsult为返回内容
@AfterReturning(value="Pointcut()",returning="result")
public void afterReturningMethod(JoinPoint joinPoint,Object result){
log.info("调用了返回通知");
}
//@AfterThrowing: 异常通知
@AfterThrowing(value="Pointcut()",throwing="e")
public void afterReturningMethod(JoinPoint joinPoint, Exception e){
log.info("调用了异常通知");
}
//@Around：环绕通知
@Around("Pointcut()")
public Object Around(ProceedingJoinPoint pjp) throws Throwable {
log.info("around执行方法之前");
Object object = pjp.proceed();
log.info("around执行方法之后--返回值：" +object);
return object;
}
}@RestController
@Slf4j
public class MessageController {
@RequestMapping(value="/send_message",produces = "text/json;charset=UTF-8")
public String send_message(MessagePojo pojo) throws Exception {
log.info("执行了controller.send_message方法");
return JSON.toJSONString(pojo);
}
}在浏览器输入：http://localhost:9999/send_message?delay=15&className=B</a></p>
可看到打印
可以看到，aspect类内部的 advice 将按照以下的顺序进行执行
@Aspect
@Component
@Slf4j
public class TestAspect {
//com.kzj.kzj_rabbitmq.controller 包中所有的类的所有方法切面
//@Pointcut("execution(public com.kzj.kzj_rabbitmq.controller..(..))")
//只针对 MessageController 类切面
//@Pointcut("execution(public com.kzj.kzj_rabbitmq.controller.MessageController.(..))")
//统一切点,对com.kzj.kzj_rabbitmq.controller及其子包中所有的类的所有方法切面
@Pointcut("execution(public com.kzj.kzj_rabbitmq.controller...(..))")
public void Pointcut() {
}
//@Around：环绕通知
@Around("Pointcut()")
public Object Around(ProceedingJoinPoint pjp) throws Throwable {
Map<String,Object> data = new HashMap<>();
//获取目标类名称
String clazzName = pjp.getTarget().getClass().getName();
//获取目标类方法名称
String methodName = pjp.getSignature().getName();
//记录类名称
data.put("clazzName",clazzName);
//记录对应方法名称
data.put("methodName",methodName);
//记录请求参数
data.put("params",pjp.getArgs());
//开始调用时间
// 计时并调用目标函数
long start = System.currentTimeMillis();
Object result = pjp.proceed();
Long time = System.currentTimeMillis() - start;
//记录返回参数
data.put("result",result);
//设置消耗总时间
data.put("consumeTime",time);
System.out.println(data);
return result;
}
}