带参数的Spring MVC异步控制器实现

Question

根据这篇博客，可以避免阻止HTTP请求线程等待更长的IO，使其异步。 在这里，单独的线程负责在结果可用时返回结果。 基本实现如下

@RestController
public class RequestController {

  private final TaskService taskService;

  private final Logger logger = LoggerFactory.getLogger(this.getClass());


  @Autowired
  public RequestController(TaskService taskService) {
    this.taskService = taskService;
  }

  @RequestMapping(value = "/callable", method = RequestMethod.GET, produces = "text/html")
  public Callable<String> executeSlowTaskWithCallable() {
    logger.info("Request received");
    Callable<String> callable = taskService::execute;
    logger.info("Servlet thread released");

    return callable;
  }
  :
}

而不是“执行”（不带参数并返回结果），我想创建Callable使用带参数的方法并返回一些结果。 喜欢

Callable<String> callable = taskService.execute(request, headers);

怎么做到这一点？

Answer 1

只需使用lambda：

Callable<String> callable = () -> taskService.execute(request, headers);

像这样：

@RestController
public class RequestController {

  private final Logger logger = LoggerFactory.getLogger(this.getClass());
  private final TaskService taskService;

  @Autowired
  public RequestController(TaskService taskService) {
    this.taskService = taskService;
  }

  @RequestMapping(value = "/callable", method = RequestMethod.GET, produces = "text/html")
  public Callable<String> executeSlowTaskWithCallable() {
    logger.info("Request received");
    Object request, headers = // initialize variables
    Callable<String> callable = () -> taskService.execute(request, headers);
    logger.info("Servlet thread released");

    return callable;
  }

}