import org.aspectj.lang.ProceedingJoinPoint; import org.aspectj.lang.annotation.Around; import org.aspectj.lang.annotation.Aspect; import org.aspectj.lang.annotation.Pointcut; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Component; import com.big.data.crawler.leader.zk.ZKCrawlerLeaderService; @Aspect @Component public class JudgeLeaderAspect { private static final Logger logger = LoggerFactory .getLogger(JudgeLeaderAspect.class); @Autowired private ZKCrawlerLeaderService zKCrawlerLeaderService; //拦截类StoreRelationService中所有已job结尾的方法 @Pointcut("execution(public * com.big.data.crawler.scheduler.store.StoreRelationService.*Job(..))") public void isLeader(){} @Around("isLeader()") //@Before("isLeader()") 该注解不能阻止目标方法的执行 public void doBefore(ProceedingJoinPoint joinPoint) throws Throwable{ if(!zKCrawlerLeaderService.isLeader()) { logger.info("本节点不是主节点,放弃调度任务"); }else { joinPoint.proceed(); } } }
1、跟springboot结合,在pom中引入依赖
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-aop</artifactId>
</dependency>
2、定义一个切面类,加上注解
@Aspect @Component public class JudgeLeaderAspect {}
3、@Before注解只能在方法之前前做一些事,不能阻止方法的执行
如果需要阻止方法的执行,请用@Around注解