开启掘金成长之旅！这是我参与「掘金日新计划 · 12 月更文挑战」的第30天，点击查看活动详情
1.pom.xml引入依赖
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
2.启动类添加开启异步注解
3.创建异步包(Async)并且新建AsynService类
4.编辑AsyncService类
@Slf4j
@Service
public class AsyncService {
@Async
//无返回值的异步任务
public void asyncProcess() throws InterruptedException{
log.info("async process task ,current thread name {}",Thread.currentThread().getName());
TimeUnit.SECONDS.sleep(2);
}
@Async
//定义有返回值的异步任务
public Future<Integer> asyncProcessHasReturn() throws InterruptedException{
log.info("async process task has return ,current thread name {}",Thread.currentThread().getName());
TimeUnit.SECONDS.sleep(2);
return new AsyncResult<>(100);
}
}
========================
5.config新增AsyncPoolConfig线程池配置文件
@Slf4j
@Configuration
public class AsyncPoolConfig implements AsyncConfigurer {
@Bean
@Override
public Executor getAsyncExecutor(){
ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
executor.setCorePoolSize(10);
executor.setMaxPoolSize(20);
executor.setQueueCapacity(20);
executor.setKeepAliveSeconds(60);
executor.setThreadNamePrefix("ImoocAsync_");
executor.setWaitForTasksToCompleteOnShutdown(true);
executor.setAwaitTerminationSeconds(60);
//拒绝器
executor.setRejectedExecutionHandler(new ThreadPoolExecutor.AbortPolicy()
);
executor.initialize();
return executor;
}
@Override
public AsyncUncaughtExceptionHandler getAsyncUncaughtExceptionHandler() {
return new AsyncExceptionHandler();
}
class AsyncExceptionHandler implements AsyncUncaughtExceptionHandler{
@Override
public void handleUncaughtException(Throwable throwable, Method method, Object... objects) {
log.info("AsyncError:{},Method:{},Param:{}",throwable.getMessage(),method.getName(), JSON.toJSONString(objects));
throwable.printStackTrace();
//发送邮件或者短信
}
}
代码说明：
-
@Configuration：注入配置类
-
class AsyncPoolConfig implements AsyncConfigurer：线程池配置类实现AsyncConfigurer
-
setCorePoolSize：核心线程池大小
-
setMaxPoolSize：线程池中允许的最大线程数
-
setQueueCapacity：线程池中使用的缓冲队列大小
-
setKeepAliveSeconds：空闲线程存活时间
-
setThreadNamePrefix：线程名称前缀
-
setWaitForTasksToCompleteOnShutdown：该方法用来设置线程池关闭的时候等待所有任务都完成后，再继续销毁其他的Bean，这样这些异步任务的销毁就会先于数据库连接池对象的销毁
-
setAwaitTerminationSeconds(60):** 该方法用来设置线程池中 任务的等待时间，如果超过这个时间还没有销毁就 强制销毁，以确保应用最后能够被关闭，而不是阻塞住。
-
setRejectedExecutionHandler：拒绝器策略
-
executor.initialize()：初始化线程池
-
AsyncUncaughtExceptionHandler：异步线程异常类
-
public void handleUncaughtException(Throwable throwable, Method method, Object... objects)：重写异常类，可以捕获无返回值的异常
