Package org.springframework.messaging.handler.invocation

Class AbstractAsyncReturnValueHandler

java.lang.Object

org.springframework.messaging.handler.invocation.AbstractAsyncReturnValueHandler

All Implemented Interfaces:

AsyncHandlerMethodReturnValueHandler, HandlerMethodReturnValueHandler

Direct Known Subclasses:

CompletableFutureReturnValueHandler, ListenableFutureReturnValueHandler, ReactiveReturnValueHandler

public abstract class AbstractAsyncReturnValueHandler
extends Object
implements AsyncHandlerMethodReturnValueHandler

Convenient base class for AsyncHandlerMethodReturnValueHandler implementations that support only asynchronous (Future-like) return values and merely serve as adapters of such types to Spring's ListenableFuture.

Since:

4.2

Author:

Sebastien Deleuze

Constructor Summary

Constructors

Constructor	Description
AbstractAsyncReturnValueHandler()

Method Summary

Modifier and Type	Method	Description
void	handleReturnValue(Object returnValue, MethodParameter returnType, Message<?> message)	Handle the given return value.
boolean	isAsyncReturnValue(Object returnValue, MethodParameter returnType)	Whether the return value represents an asynchronous, Future-like type with success and error callbacks.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.springframework.messaging.handler.invocation.AsyncHandlerMethodReturnValueHandler

toCompletableFuture, toListenableFuture

Methods inherited from interface org.springframework.messaging.handler.invocation.HandlerMethodReturnValueHandler

supportsReturnType

Constructor Details

AbstractAsyncReturnValueHandler

public AbstractAsyncReturnValueHandler()

Method Details

isAsyncReturnValue

public boolean isAsyncReturnValue(Object returnValue,
 MethodParameter returnType)

Description copied from interface: AsyncHandlerMethodReturnValueHandler

Whether the return value represents an asynchronous, Future-like type with success and error callbacks. If this method returns true, then AsyncHandlerMethodReturnValueHandler.toCompletableFuture(java.lang.Object, org.springframework.core.MethodParameter) is invoked next. If it returns false, then HandlerMethodReturnValueHandler.handleReturnValue(java.lang.Object, org.springframework.core.MethodParameter, org.springframework.messaging.Message<?>) is called.

Note: this method will only be invoked after HandlerMethodReturnValueHandler.supportsReturnType(org.springframework.core.MethodParameter) is called and it returns true.

Specified by:

isAsyncReturnValue in interface AsyncHandlerMethodReturnValueHandler

Parameters:

returnValue - the value returned from the handler method

returnType - the type of the return value

Returns:

true if the return value type represents an async value

handleReturnValue

public void handleReturnValue(@Nullable
 Object returnValue,
 MethodParameter returnType,
 Message<?> message)

Description copied from interface: HandlerMethodReturnValueHandler

Handle the given return value.

Specified by:

handleReturnValue in interface HandlerMethodReturnValueHandler

Parameters:

returnValue - the value returned from the handler method

returnType - the type of the return value. This type must have previously been passed to HandlerMethodReturnValueHandler.supportsReturnType(org.springframework.core.MethodParameter) and it must have returned true.

message - the message that caused this method to be called