content: package com.genersoft.iot.vmp.conf;
  
  import org.springframework.context.annotation.Bean;
  import org.springframework.context.annotation.Configuration;
  import org.springframework.core.annotation.Order;
  import org.springframework.scheduling.annotation.EnableAsync;
  import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
  
  import java.util.concurrent.ThreadPoolExecutor;
  
  /**
   *  ThreadPoolTask 配置类
   * @author lin
   */
  @Configuration
  @Order(1)
  @EnableAsync(proxyTargetClass = true)
  public class ThreadPoolTaskConfig {
  
      public static final int cpuNum = Runtime.getRuntime().availableProcessors();
  
      /**
       *   默认情况下，在创建了线程池后，线程池中的线程数为0，当有任务来之后，就会创建一个线程去执行任务，
       *    当线程池中的线程数目达到corePoolSize后，就会把到达的任务放到缓存队列当中；
       *  当队列满了，就继续创建线程，当线程数量大于等于maxPoolSize后，开始使用拒绝策略拒绝
       */
  
      /**
       * 核心线程数（默认线程数）
       */
      private static final int corePoolSize = Math.max(cpuNum * 2, 16);
      /**
       * 最大线程数
       */
      private static final int maxPoolSize = corePoolSize * 10;
      /**
       * 允许线程空闲时间（单位：默认为秒）
       */
      private static final int keepAliveTime = 30;
  
      /**
       * 缓冲队列大小
       */
      private static final int queueCapacity = 10000;
      /**
       * 线程池名前缀
       */
      private static final String threadNamePrefix = "async-";
  
  
      @Bean("taskExecutor") // bean的名称，默认为首字母小写的方法名
      public ThreadPoolTaskExecutor taskExecutor() {
          ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
          executor.setCorePoolSize(corePoolSize);
          executor.setMaxPoolSize(maxPoolSize);
          executor.setQueueCapacity(queueCapacity);
          executor.setKeepAliveSeconds(keepAliveTime);
          executor.setThreadNamePrefix(threadNamePrefix);
  
          // 线程池对拒绝任务的处理策略
          // CallerRunsPolicy：由调用线程（提交任务的线程）处理该任务
          executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
          // 初始化
          executor.initialize();
          return executor;
      }
  }
  