org.springframework.web.servlet.mvc.method.annotation

Class ResponseBodyEmitterReturnValueHandler

java.lang.Object

org.springframework.web.servlet.mvc.method.annotation.ResponseBodyEmitterReturnValueHandler

All Implemented Interfaces:

HandlerMethodReturnValueHandler

public class ResponseBodyEmitterReturnValueHandler
extends Object
implements HandlerMethodReturnValueHandler

Handler for return values of type ResponseBodyEmitter and sub-classes such as SseEmitter including the same types wrapped with ResponseEntity.

As of 5.0 also supports reactive return value types for any reactive library with registered adapters in ReactiveAdapterRegistry.

Since:

4.2

Author:

Rossen Stoyanchev

Constructor Summary

Constructors

Constructor and Description
ResponseBodyEmitterReturnValueHandler(List<HttpMessageConverter<?>> messageConverters) Simple constructor with reactive type support based on a default instance of ReactiveAdapterRegistry, SyncTaskExecutor, and ContentNegotiationManager with an Accept header strategy.
ResponseBodyEmitterReturnValueHandler(List<HttpMessageConverter<?>> messageConverters, ReactiveAdapterRegistry registry, TaskExecutor executor, ContentNegotiationManager manager) Complete constructor with pluggable "reactive" type support.

Method Summary

Modifier and Type	Method and Description
void	handleReturnValue(Object returnValue, MethodParameter returnType, ModelAndViewContainer mavContainer, NativeWebRequest webRequest) Handle the given return value by adding attributes to the model and setting a view or setting the ModelAndViewContainer.setRequestHandled(boolean) flag to true to indicate the response has been handled directly.
boolean	supportsReturnType(MethodParameter returnType) Whether the given method return type is supported by this handler.

Methods inherited from class java.lang.Object

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

Constructor Detail

ResponseBodyEmitterReturnValueHandler

public ResponseBodyEmitterReturnValueHandler(List<HttpMessageConverter<?>> messageConverters)

Simple constructor with reactive type support based on a default instance of ReactiveAdapterRegistry, SyncTaskExecutor, and ContentNegotiationManager with an Accept header strategy.

ResponseBodyEmitterReturnValueHandler

public ResponseBodyEmitterReturnValueHandler(List<HttpMessageConverter<?>> messageConverters,
                                             ReactiveAdapterRegistry registry,
                                             TaskExecutor executor,
                                             ContentNegotiationManager manager)

Complete constructor with pluggable "reactive" type support.

Parameters:

messageConverters - converters to write emitted objects with

registry - for reactive return value type support

executor - for blocking I/O writes of items emitted from reactive types

manager - for detecting streaming media types

Since:

5.0

Method Detail

supportsReturnType

public boolean supportsReturnType(MethodParameter returnType)

Description copied from interface: HandlerMethodReturnValueHandler

Whether the given method return type is supported by this handler.

Specified by:

supportsReturnType in interface HandlerMethodReturnValueHandler

Parameters:

returnType - the method return type to check

Returns:

true if this handler supports the supplied return type; false otherwise

handleReturnValue

public void handleReturnValue(@Nullable
                              Object returnValue,
                              MethodParameter returnType,
                              ModelAndViewContainer mavContainer,
                              NativeWebRequest webRequest)
                       throws Exception

Description copied from interface: HandlerMethodReturnValueHandler

Handle the given return value by adding attributes to the model and setting a view or setting the ModelAndViewContainer.setRequestHandled(boolean) flag to true to indicate the response has been handled directly.

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) which must have returned true.

mavContainer - the ModelAndViewContainer for the current request

webRequest - the current request

Throws:

Exception - if the return value handling results in an error