spring之并发线程池 ThreadPoolTaskExcutor

#一先说一些关键性的东西。

当 PoolSize<CorePoolSize 时增加 PoolSize;
当队列大小 < QueueCapacity 时由当前线程池执行 workQueue.offer(command)；
当 PoolSize >= CorePoolSize && PoolSize<MaxPoolSize 时，且队列大小 >=QueueCapacity 时，新增线程数量，但大小必须 < MaxPoolSize.
KeepAliveTime 是线程是否退出的衡量时间，但核心线程是否退出还要看 allowCoreThreadTimeOut

else if (poolSize > corePoolSize || allowCoreThreadTimeOut)  
                    r = workQueue.poll(keepAliveTime, TimeUnit.NANOSECONDS);

#二下面是重点，Spring 中 ThreadPoolTaskExcutor

##1 异步配置类，为下边的异步注入提供配置

@EnableAsync
@Configuration
@ComponentScan("org.sselab.conf")
public class TaskConfig implements AsyncConfigurer {
    @Override
    public Executor getAsyncExecutor() {
        ThreadPoolTaskExecutor executor=new ThreadPoolTaskExecutor();
        executor.setCorePoolSize(5);
        executor.setMaxPoolSize(10);
        executor.setQueueCapacity(25);
        executor.initialize();
        return executor;
    }

    @Override
    public AsyncUncaughtExceptionHandler getAsyncUncaughtExceptionHandler() {
        return null;
  }
}

##2 异步执行类

@Service
public class AsyncTaskService {
    @Async              //该注解若放到类上，标明该类下所有方法均为异步类。这里的方法自动被注入了ThreadPoolTasjkExcuter
    public void excuteAsyncTask(Integer i){
        System.out.println("执行异步任务:"+i);
    }
    @Async
    public void excuteAsyncTaskPlus(Integer i){
        System.out.println("执行异步任务+1:"+(i+1));
    }
}

##3 启动函数

public class AsyncMain {
    public static void main(String[] args) {
        AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(TaskConfig.class);
        AsyncTaskService taskService = context.getBean(AsyncTaskService.class);
        for (int i = 0; i < 10; i++) {
            taskService.excuteAsyncTask(i);
            taskService.excuteAsyncTaskPlus(i);
        }
        context.close();
    }
}

4 结果

10:08:22.505 [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory - Destroying singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@617faa95: defining beans [org.springframework.context.annotation.internalConfigurationAnnotationProcessor,org.springframework.context.annotation.internalAutowiredAnnotationProcessor,org.springframework.context.annotation.internalRequiredAnnotationProcessor,org.springframework.context.annotation.internalCommonAnnotationProcessor,org.springframework.context.event.internalEventListenerProcessor,org.springframework.context.event.internalEventListenerFactory,taskConfig,org.springframework.context.annotation.ConfigurationClassPostProcessor.importAwareProcessor,org.springframework.context.annotation.ConfigurationClassPostProcessor.enhancedConfigurationProcessor,asyncTaskService,org.springframework.scheduling.annotation.ProxyAsyncConfiguration,org.springframework.context.annotation.internalAsyncAnnotationProcessor]; root of factory hierarchy
执行异步任务+1:2
执行异步任务+1:3
执行异步任务+1:1
执行异步任务+1:4
执行异步任务:4
执行异步任务:1
执行异步任务:2
执行异步任务+1:6
执行异步任务:6
执行异步任务+1:7
执行异步任务:7
执行异步任务:3
执行异步任务+1:8
执行异步任务:5
执行异步任务:0
执行异步任务+1:5
执行异步任务+1:10
执行异步任务:9
执行异步任务+1:9
执行异步任务:8

来源：oschina

链接：https://my.oschina.net/u/2861598/blog/785492

标签

异步队列

线程池