Spring boot多线程

1、配置线程配置类

package test;

import java.util.concurrent.Executor;

import org.springframework.aop.interceptor.AsyncUncaughtExceptionHandler;
import org.springframework.context.annotation.ComponentScan;
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
@ComponentScan("test")
@EnableAsync
// 线程配置类
public class AsyncTaskConfig implements AsyncConfigurer {

    // ThredPoolTaskExcutor的处理流程
    // 当池子大小小于corePoolSize，就新建线程，并处理请求
    // 当池子大小等于corePoolSize，把请求放入workQueue中，池子里的空闲线程就去workQueue中取任务并处理
    // 当workQueue放不下任务时，就新建线程入池，并处理请求，如果池子大小撑到了maximumPoolSize，就用RejectedExecutionHandler来做拒绝处理
    // 当池子的线程数大于corePoolSize时，多余的线程会等待keepAliveTime长时间，如果无请求可处理就自行销毁

    @Override
    public Executor getAsyncExecutor() {
        ThreadPoolTaskExecutor taskExecutor = new ThreadPoolTaskExecutor();
        taskExecutor.setCorePoolSize(5);// 最小线程数
        taskExecutor.setMaxPoolSize(10);// 最大线程数
        taskExecutor.setQueueCapacity(25);// 等待队列

        taskExecutor.initialize();

        return taskExecutor;
    }

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

2、定义线程执行任务类

package test;

import java.util.Random;
import java.util.concurrent.Future;

import org.springframework.scheduling.annotation.Async;
import org.springframework.scheduling.annotation.AsyncResult;
import org.springframework.stereotype.Service;

@Service
// 线程执行任务类
public class AsyncTaskService {

    Random random = new Random();// 默认构造方法

    @Async
    // 表明是异步方法
    // 无返回值
    public void executeAsyncTask(Integer i) {
        System.out.println("执行异步任务：" + i);
    }

    /**
     * 异常调用返回Future
     * 
     * @param i
     * @return
     * @throws InterruptedException
     */
    @Async
    public Future<String> asyncInvokeReturnFuture(int i) throws InterruptedException {
        System.out.println("input is " + i);
        Thread.sleep(1000 * random.nextInt(i));

        Future<String> future = new AsyncResult<String>("success:" + i);// Future接收返回值，这里是String类型，可以指明其他类型

        return future;
    }
}

3、调用

package test;

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Future;

import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.core.task.TaskRejectedException;

public class Application {

    public static void main(String[] args) throws InterruptedException, ExecutionException {
        // testVoid();

        testReturn();
    }

    // 测试无返回结果
    private static void testVoid() {
        AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(AsyncTaskConfig.class);
        AsyncTaskService asyncTaskService = context.getBean(AsyncTaskService.class);

        // 创建了20个线程
        for (int i = 1; i <= 20; i++) {
            asyncTaskService.executeAsyncTask(i);
        }

        context.close();
    }

    // 测试有返回结果
    private static void testReturn() throws InterruptedException, ExecutionException {
        AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(AsyncTaskConfig.class);
        AsyncTaskService asyncTaskService = context.getBean(AsyncTaskService.class);

        List<Future<String>> lstFuture = new ArrayList<Future<String>>();// 存放所有的线程，用于获取结果

        // 创建100个线程
        for (int i = 1; i <= 100; i++) {
            while (true) {
                try {
                    // 线程池超过最大线程数时，会抛出TaskRejectedException，则等待1s，直到不抛出异常为止
                    Future<String> future = asyncTaskService.asyncInvokeReturnFuture(i);
                    lstFuture.add(future);

                    break;
                } catch (TaskRejectedException e) {
                    System.out.println("线程池满，等待1S。");
                    Thread.sleep(1000);
                }
            }
        }

        // 获取值。get是阻塞式，等待当前线程完成才返回值
        for (Future<String> future : lstFuture) {
            System.out.println(future.get());
        }

        context.close();
    }
}

maven配置

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>TestAysc</groupId>
  <artifactId>TestAysc</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <dependencies>
      <dependency>
          <groupId>org.springframework.boot</groupId>
          <artifactId>spring-boot</artifactId>
          <version>1.5.6.RELEASE</version>
      </dependency>
      <dependency>
          <groupId>org.springframework</groupId>
          <artifactId>spring-aop</artifactId>
          <version>4.3.10.RELEASE</version>
      </dependency>
  </dependencies>
</project>

 结果展示：

1、无返回结果

2、有返回结果