【转】non-blocking REST services with Spring MVC

堵塞Controller

1. Controller为单例；
2. 非线程安全；
3. 堵塞方式；
4. 1个request对应1个处理Thread；

@RestController
public class ProcessingController {

  @RequestMapping("/process-blocking")
  public ProcessingStatus blockingProcessing(...) {
    ...
    return new ProcessingStatus(...);
  }
}

非阻塞

@RestController
public class ProcessingController {

  @RequestMapping("/process-non-blocking")
  public DeferredResult<ProcessingStatus> nonBlockingProcessing(...) {

    // Initiate the processing in another thread
    DeferredResult<ProcessingStatus> deferredResult = new DeferredResult<>();
    ProcessingTask task = new ProcessingTask(deferredResult, ...);
    dispatch(task);

    // Return to let go of the precious thread we are holding on to...
    return deferredResult;
  }
}

public class ProcessingTask extends SomeCallbackInterface {

  private DeferredResult<ProcessingStatus> deferredResult;

  public ProcessingTask(DeferredResult<ProcessingStatus> deferredResult, ...) {
    this.deferredResult = deferredResult;
    ...
  }

  @Override
  public void done() {
    if (deferredResult.isSetOrExpired()) {
      LOG.warn("Processing of non-blocking request already expired");
    } else {
      boolean deferredStatus = deferredResult.setResult(new ProcessingStatus(...));
    }
  }
}

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原文链接

Developing non-blocking REST services with Spring MVC