Spring|Spring boot @Async @EnableAsync 注解实现多线程 Springboot@Async@EnableAsync注解实现

2019独角兽企业重金招聘Python工程师标准>>>
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多线程执行过程

1. 如果此时线程池中的数量小于corePoolSize，即使线程池中的线程都处于空闲状态，也要创建新的线程来处理被添加的任务。 2. 如果此时线程池中的数量等于corePoolSize，但是缓冲队列 workQueue未满，那么任务被放入缓冲队列。 3. 如果此时线程池中的数量大于corePoolSize，缓冲队列workQueue满，并且线程池中的数量小于maxPoolSize，建新的线程来处理被添加的任务。 4. 如果此时线程池中的数量大于corePoolSize，缓冲队列workQueue满，并且线程池中的数量等于maxPoolSize，那么通过handler所指定的策略来处理此任务。也就是：处理任务的优先级为：核心线程corePoolSize、任务队列workQueue、最大线程 maximumPoolSize，如果三者都满了，使用handler处理被拒绝的任务。 5. 当线程池中的线程数量大于corePoolSize时，如果某线程空闲时间超过keepAliveTime，线程将被终止。这样，线程池可以动态的调整池中的线程数。

配置类

/** * [@author](https://my.oschina.net/arthor) Mr.Krab * [@date](https://my.oschina.net/u/2504391) 2019-03-05 09:39 */ @Configuration @EnableAsync // 启用多线程 public class AsyncConfig {[@Bean](https://my.oschina.net/bean) public Executor getExecutor() { ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor(); // 线程池维护线程的最少数量 executor.setCorePoolSize(5); // 线程池维护线程的最大数量 executor.setMaxPoolSize(10); // 缓存队列 executor.setQueueCapacity(25); // 线程池初始化 executor.initialize(); return executor; } }

异步任务

/** * @author Mr.Krab * @date 2019-03-05 09:45 */ @Service @Slf4j public class AsyncService {@Async //异步任务 public void executeAsync(int i) { log.info("current thread {}, i = {}", Thread.currentThread().getName(), i); } }

【Spring|Spring boot @Async @EnableAsync 注解实现多线程】测试类

/** * @author Mr.Krab * @date 2019-03-05 09:48 */ @RunWith(SpringRunner.class) @SpringBootTest public class AsyncTest {@Autowired private AsyncService asyncService; @Test public void testAsync(){ for(int i =0; i< 10; i++){ asyncService.executeAsync(i); }} }

执行结果

2019-03-05 09:55:10.470INFO 18644 --- [getExecutor-4] cn.misterkrab.demo.async.AsyncService: current thread getExecutor-4, i = 3 2019-03-05 09:55:10.470INFO 18644 --- [getExecutor-5] cn.misterkrab.demo.async.AsyncService: current thread getExecutor-5, i = 4 2019-03-05 09:55:10.470INFO 18644 --- [getExecutor-1] cn.misterkrab.demo.async.AsyncService: current thread getExecutor-1, i = 0 2019-03-05 09:55:10.470INFO 18644 --- [getExecutor-3] cn.misterkrab.demo.async.AsyncService: current thread getExecutor-3, i = 2 2019-03-05 09:55:12.163INFO 18644 --- [getExecutor-1] cn.misterkrab.demo.async.AsyncService: current thread getExecutor-1, i = 7 2019-03-05 09:55:10.470INFO 18644 --- [getExecutor-2] cn.misterkrab.demo.async.AsyncService: current thread getExecutor-2, i = 1 2019-03-05 09:55:11.019INFO 18644 --- [getExecutor-4] cn.misterkrab.demo.async.AsyncService: current thread getExecutor-4, i = 5 2019-03-05 09:55:11.715INFO 18644 --- [getExecutor-5] cn.misterkrab.demo.async.AsyncService: current thread getExecutor-5, i = 6 2019-03-05 09:55:12.587INFO 18644 --- [getExecutor-3] cn.misterkrab.demo.async.AsyncService: current thread getExecutor-3, i = 8 2019-03-05 09:55:13.651INFO 18644 --- [getExecutor-1] cn.misterkrab.demo.async.AsyncService: current thread getExecutor-1, i = 9

转载于:https://my.oschina.net/u/3757402/blog/3017980