一、介绍
spring是通过任务执行器(TaskExecutor)来实现多线程和并发编程,使用ThreadPoolTaskExecutor来创建一个基于线城池的TaskExecutor。在使用线程池的大多数情况下都是异步非阻塞的。我们配置注解@EnableAsync可以开启异步任务。然后在实际执行的方法上配置注解@Async上声明是异步任务。
package com.spartajet.springbootlearn.thread; import org.springframework.aop.interceptor.AsyncUncaughtExceptionHandler; import org.springframework.context.annotation.Configuration; import org.springframework.scheduling.annotation.AsyncConfigurer; import org.springframework.scheduling.annotation.EnableAsync; import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor; import java.util.concurrent.Executor; /** * @description * @create 2017-02-22 下午11:53 * @email gxz04220427@163.com */ @Configuration @EnableAsync public class ThreadConfig implements AsyncConfigurer { /** * The {@link Executor} instance to be used when processing async * method invocations. */ @Override public Executor getAsyncExecutor() { ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor(); executor.setCorePoolSize(5); executor.setMaxPoolSize(15); executor.setQueueCapacity(25); executor.initialize(); return executor; } /** * The {@link AsyncUncaughtExceptionHandler} instance to be used * when an exception is thrown during an asynchronous method execution * with {@code void} return type. */ @Override public AsyncUncaughtExceptionHandler getAsyncUncaughtExceptionHandler() { return null; } }
解读:
利用EnableAsync来开启Springboot对于异步任务的支持
配置类实现接口AsyncConfigurator,返回一个ThreadPoolTaskExecutor线程池对象。
三、任务执行
任务执行代码:
package com.spartajet.springbootlearn.thread; import org.springframework.scheduling.annotation.Async; import org.springframework.stereotype.Service; /** * @description * @create 2017-02-23 上午12:00 * @email gxz04220427@163.com */ @Service public class AsyncTaskService { @Async public void executeAsyncTask(int i) { System.out.println("线程" + Thread.currentThread().getName() + " 执行异步任务:" + i); } }
代码解读:
通过@Async注解表明该方法是异步方法,如果注解在类上,那表明这个类里面的所有方法都是异步的。
四、测试代码
package com.spartajet.springbootlearn; import com.spartajet.springbootlearn.thread.AsyncTaskService; import org.junit.Test; import org.junit.runner.RunWith; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.test.context.SpringBootTest; import org.springframework.test.context.junit4.SpringRunner; @RunWith (SpringRunner.class) @SpringBootTest public class SpringbootLearnApplicationTests { @Autowired private AsyncTaskService asyncTaskService; @Test public void contextLoads() { } @Test public void threadTest() { for (int i = 0; i < 20; i++) { asyncTaskService.executeAsyncTask(i); } } }
测试结果:
线程ThreadPoolTaskExecutor-4 执行异步任务:3
线程ThreadPoolTaskExecutor-2 执行异步任务:1
线程ThreadPoolTaskExecutor-1 执行异步任务:0
线程ThreadPoolTaskExecutor-1 执行异步任务:7
线程ThreadPoolTaskExecutor-1 执行异步任务:8
线程ThreadPoolTaskExecutor-1 执行异步任务:9
线程ThreadPoolTaskExecutor-1 执行异步任务:10
线程ThreadPoolTaskExecutor-5 执行异步任务:4
线程ThreadPoolTaskExecutor-3 执行异步任务:2
线程ThreadPoolTaskExecutor-5 执行异步任务:12
线程ThreadPoolTaskExecutor-1 执行异步任务:11
线程ThreadPoolTaskExecutor-2 执行异步任务:6
线程ThreadPoolTaskExecutor-4 执行异步任务:5
线程ThreadPoolTaskExecutor-2 执行异步任务:16
线程ThreadPoolTaskExecutor-1 执行异步任务:15
线程ThreadPoolTaskExecutor-5 执行异步任务:14
线程ThreadPoolTaskExecutor-3 执行异步任务:13
线程ThreadPoolTaskExecutor-1 执行异步任务:19
线程ThreadPoolTaskExecutor-2 执行异步任务:18
线程ThreadPoolTaskExecutor-4 执行异步任务:17
总结
以上所述是给大家介绍的Springboot对多线程的支持,希望对大家有所帮助,如果大家有任何疑问请给我留言!