Spring Boot2.x 使用多线程

╰+哭是因爲堅強的太久メ 2022-04-24 16:26 205阅读 0赞

*  关于Spring Boot多线程  
    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。
 *  配置类代码如下
    
     *  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。

import java.util.concurrent.Executor;
    
    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;
    
    @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;
        }
    }

*  任务执行
    
     *  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。

import org.springframework.scheduling.annotation.Async;
    import org.springframework.stereotype.Service;
    
    @Service
    public class AsyncTaskService {
        @Async
        public void executeAsyncTask(int i) {
            System.out.println("Thread" + Thread.currentThread().getName() + " run：" + i);
        }
    }

*  测试代码

@RunWith(SpringRunner.class)
    @SpringBootTest
    public class ThreadApplicationTests {
    
    	@Autowired
        private AsyncTaskService asyncTaskService;
    
        @Test
        public void contextLoads() {
        }
    
        @Test
        public void threadTest() {
            for (int i = 0; i < 5; i++) {
                asyncTaskService.executeAsyncTask(i);
            }
        }
    }

*  输出

ThreadThreadPoolTaskExecutor-1 run：0
    ThreadThreadPoolTaskExecutor-5 run：4
    ThreadThreadPoolTaskExecutor-4 run：3
    ThreadThreadPoolTaskExecutor-2 run：1
    ThreadThreadPoolTaskExecutor-3 run：2