Class ServerSentEventHttpMessageWriter

java.lang.Object

org.springframework.http.codec.ServerSentEventHttpMessageWriter

All Implemented Interfaces:

HttpMessageWriter<Object>

public class ServerSentEventHttpMessageWriter
extends Object
implements HttpMessageWriter<Object>

HttpMessageWriter for "text/event-stream" responses.

Since:

5.0

Author:

Sebastien Deleuze, Arjen Poutsma, Rossen Stoyanchev

Constructor Summary

Constructors

Constructor	Description
ServerSentEventHttpMessageWriter()	Constructor without an Encoder.
ServerSentEventHttpMessageWriter(@Nullable org.springframework.core.codec.Encoder<?> encoder)	Constructor with JSON Encoder for encoding objects.

Method Summary

Modifier and Type	Method	Description
boolean	canWrite(org.springframework.core.ResolvableType elementType, @Nullable MediaType mediaType)	Whether the given object type is supported by this writer.
@Nullable org.springframework.core.codec.Encoder<?>	getEncoder()	Return the configured Encoder, if any.
List<MediaType>	getWritableMediaTypes()	Return the list of media types supported by this Writer.
Mono<Void>	write(Publisher<?> input, org.springframework.core.ResolvableType actualType, org.springframework.core.ResolvableType elementType, @Nullable MediaType mediaType, ServerHttpRequest request, ServerHttpResponse response, Map<String,Object> hints)	Server-side only alternative to HttpMessageWriter.write(Publisher, ResolvableType, MediaType, ReactiveHttpOutputMessage, Map) with additional context available.
Mono<Void>	write(Publisher<?> input, org.springframework.core.ResolvableType elementType, @Nullable MediaType mediaType, ReactiveHttpOutputMessage message, Map<String,Object> hints)	Write a given stream of object to the output message.

Methods inherited from class Object

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

Methods inherited from interface HttpMessageWriter

getWritableMediaTypes

Constructor Details

ServerSentEventHttpMessageWriter

public ServerSentEventHttpMessageWriter()

Constructor without an Encoder. In this mode only String is supported for event data to be encoded.

ServerSentEventHttpMessageWriter

public ServerSentEventHttpMessageWriter(@Nullable org.springframework.core.codec.Encoder<?> encoder)

Constructor with JSON Encoder for encoding objects. Support for String event data is built-in.

Parameters:

encoder - the Encoder to use (may be null)

Method Details

getEncoder

public @Nullable org.springframework.core.codec.Encoder<?> getEncoder()

Return the configured Encoder, if any.

getWritableMediaTypes

public List<MediaType> getWritableMediaTypes()

Description copied from interface: HttpMessageWriter

Return the list of media types supported by this Writer. The list may not apply to every possible target element type and calls to this method should typically be guarded via canWrite(elementType, null). The list may also exclude media types supported only for a specific element type. Alternatively, use HttpMessageWriter.getWritableMediaTypes(ResolvableType) for a more precise list.

Specified by:

getWritableMediaTypes in interface HttpMessageWriter<Object>

Returns:

the general list of supported media types

canWrite

public boolean canWrite(org.springframework.core.ResolvableType elementType,
 @Nullable MediaType mediaType)

Description copied from interface: HttpMessageWriter

Whether the given object type is supported by this writer.

Specified by:

canWrite in interface HttpMessageWriter<Object>

Parameters:

elementType - the type of object to check

mediaType - the media type for the write (possibly null)

Returns:

true if writable, false otherwise

write

public Mono<Void> write(Publisher<?> input,
 org.springframework.core.ResolvableType elementType,
 @Nullable MediaType mediaType,
 ReactiveHttpOutputMessage message,
 Map<String,Object> hints)

Description copied from interface: HttpMessageWriter

Write a given stream of object to the output message.

Specified by:

write in interface HttpMessageWriter<Object>

Parameters:

input - the objects to write

elementType - the type of objects in the stream which must have been previously checked via HttpMessageWriter.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

public Mono<Void> write(Publisher<?> input,
 org.springframework.core.ResolvableType actualType,
 org.springframework.core.ResolvableType elementType,
 @Nullable MediaType mediaType,
 ServerHttpRequest request,
 ServerHttpResponse response,
 Map<String,Object> hints)

Description copied from interface: HttpMessageWriter

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

Specified by:

write in interface HttpMessageWriter<Object>

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