如何设置@Async 方法线程优先级 - spring-boot？

Question

我在 Spring Boot 中有这个异步方法：

@Async
public void calculateResult(List matrix) {
    //do calculation
}

此方法在 controller 调用。

我想降低这个计算方法线程的优先级。 我怎么做？

Answer 1

使用异步注释你无法实现这一点。 @Async只接受自定义任务执行器。没有办法设置优先级。 但是你可以像这样手动完成：

创建这个bean：

@Bean("CustomTaskExecutor")
  public TaskExecutor threadPoolTaskExecutor(
          @Value("${spring.async.core-pool-size}") int corePoolSize,
          @Value("${spring.async.max-pool-size}") int maxPoolSize,
          @Value("${spring.async.queue-capacity}") int queueCapacity) {
    ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor() {

      @Override
      protected BlockingQueue<Runnable> createQueue(int queueCapacity) {
        return new PriorityBlockingQueue<Runnable>(queueCapacity);
      }

    };
    executor.setCorePoolSize(corePoolSize);
    executor.setMaxPoolSize(maxPoolSize);
    executor.setQueueCapacity(queueCapacity);
    return executor;
  }

优先任务：

public class Task implements Runnable {
    private Consumer<Job> jobConsumer;
    private Job job;
      public Job getJob() {
        return this.job;
      }
      public Task(Consumer<Job> jobConsumer, Job job) {
        this.jobConsumer = jobConsumer;
        this.job = job;
      }
      @Override
      public void run() {
        this.jobConsumer.accept(job);
      }
    }

未来的自定义任务：

public class FutureCustomTask extends FutureTask<FutureCustomTask> implements Comparable<FutureCustomTask> {
private Task task;
public FutureCustomTask(Task task) {
    super(task, null);
    this.task = task;
  }
@Override
  public int compareTo(FutureCustomTask o) {
    return task.getJob().getPriority().compareTo(o.task.getJob().getPriority());
  }
}

最后设置优先级如下：

@Autowired
private TaskExecutor taskExecutor;
@Autowired
private JobBusiness jobBusiness;
...
Task task = new Task(jobBusiness::performSomethingOn, job);
taskExecutor.execute(new FutureCustomTask(task));

我从这里得到了这个答案

看看这个教程也......