org.springframework.http.codec

Interface HttpMessageWriter<T>

Type Parameters:

T - the type of objects in the input stream

All Known Implementing Classes:

EncoderHttpMessageWriter, FormHttpMessageWriter, MultipartHttpMessageWriter, ResourceHttpMessageWriter, ServerSentEventHttpMessageWriter

public interface HttpMessageWriter<T>

Strategy for encoding a stream of objects of type <T> and writing the encoded stream of bytes to an ReactiveHttpOutputMessage.

Since:

5.0

Author:

Rossen Stoyanchev, Arjen Poutsma, Sebastien Deleuze

Method Summary

Modifier and Type	Method and Description
boolean	canWrite(ResolvableType elementType, MediaType mediaType) Whether the given object type is supported by this writer.
java.util.List<MediaType>	getWritableMediaTypes() Return the MediaType's that this writer supports.
<any>	write(<any> inputStream, ResolvableType elementType, MediaType mediaType, ReactiveHttpOutputMessage message, java.util.Map<java.lang.String,java.lang.Object> hints) Write an given stream of object to the output message.
default <any>	write(<any> inputStream, ResolvableType actualType, ResolvableType elementType, MediaType mediaType, ServerHttpRequest request, ServerHttpResponse response, java.util.Map<java.lang.String,java.lang.Object> hints) Server-side only alternative to #write(Publisher, ResolvableType, MediaType, ReactiveHttpOutputMessage, Map) with additional context available.

Method Detail

getWritableMediaTypes

java.util.List<MediaType> getWritableMediaTypes()

Return the MediaType's that this writer supports.

canWrite

boolean canWrite(ResolvableType elementType,
                 @Nullable
                 MediaType mediaType)

Whether the given object type is supported by this writer.

Parameters:

elementType - the type of object to check

mediaType - the media type for the write, possibly null

Returns:

true if writable, false otherwise

write

<any> write(<any> inputStream,
            ResolvableType elementType,
            @Nullable
            MediaType mediaType,
            ReactiveHttpOutputMessage message,
            java.util.Map<java.lang.String,java.lang.Object> hints)

Write an given stream of object to the output message.

Parameters:

inputStream - the objects to write

elementType - the type of objects in the stream which must have been previously checked via canWrite(ResolvableType, MediaType)

mediaType - the content type for the write, possibly null to indicate that the default content type of the writer must be used.

message - the message to write to

hints - additional information about how to encode and write

Returns:

indicates completion or error

write

default <any> write(<any> inputStream,
                    ResolvableType actualType,
                    ResolvableType elementType,
                    @Nullable
                    MediaType mediaType,
                    ServerHttpRequest request,
                    ServerHttpResponse response,
                    java.util.Map<java.lang.String,java.lang.Object> hints)

Server-side only alternative to #write(Publisher, ResolvableType, MediaType, ReactiveHttpOutputMessage, Map) with additional context available.

Parameters:

actualType - the actual return type of the method that returned the value; for annotated controllers, the MethodParameter can be accessed via ResolvableType.getSource().

elementType - the type of Objects in the input stream

mediaType - the content type to use, possibly null indicating the default content type of the writer should be used.

request - the current request

response - the current response

Returns:

a Mono that indicates completion of writing or error