Interface AsyncHandlerMethodReturnValueHandler

All Superinterfaces:

public interface AsyncHandlerMethodReturnValueHandler extends HandlerMethodReturnValueHandler
A return value handler that supports async types. Such return value types need to be handled with priority so the async value can be "unwrapped".

Note: implementing this contract is not required but it should be implemented when the handler needs to be prioritized ahead of others. For example custom (async) handlers, by default ordered after built-in handlers, should take precedence over @ResponseBody or @ModelAttribute handling, which should occur once the async value is ready. By contrast, built-in (async) handlers are already ordered ahead of sync handlers.

Rossen Stoyanchev
  • Method Details

    • isAsyncReturnValue

      boolean isAsyncReturnValue(@Nullable Object returnValue, MethodParameter returnType)
      Whether the given return value represents asynchronous computation.
      returnValue - the value returned from the handler method
      returnType - the return type
      true if the return value type represents an async value