org.springframework.http.codec

Class ServerSentEventHttpMessageWriter

java.lang.Object

org.springframework.http.codec.ServerSentEventHttpMessageWriter

All Implemented Interfaces:

HttpMessageWriter<java.lang.Object>

public class ServerSentEventHttpMessageWriter
extends java.lang.Object
implements HttpMessageWriter<java.lang.Object>

HttpMessageWriter for "text/event-stream" responses.

Since:

5.0

Author:

Sebastien Deleuze, Arjen Poutsma, Rossen Stoyanchev

Field Summary

Fields

Modifier and Type	Field and Description
private static MediaType	DEFAULT_MEDIA_TYPE
private Encoder<?>	encoder
private static java.util.List<MediaType>	WRITABLE_MEDIA_TYPES

Constructor Summary

Constructors

Constructor and Description
ServerSentEventHttpMessageWriter() Constructor without an Encoder.
ServerSentEventHttpMessageWriter(Encoder<?> encoder) Constructor with JSON Encoder for encoding objects.

Method Summary

Modifier and Type	Method and Description
boolean	canWrite(ResolvableType elementType, MediaType mediaType) Whether the given object type is supported by this writer.
private <any>	encode(<any> input, ResolvableType elementType, MediaType mediaType, DataBufferFactory factory, java.util.Map<java.lang.String,java.lang.Object> hints)
private <T> <any>	encodeData(T dataValue, ResolvableType valueType, MediaType mediaType, DataBufferFactory factory, java.util.Map<java.lang.String,java.lang.Object> hints)
private <any>	encodeText(java.lang.CharSequence text, MediaType mediaType, DataBufferFactory bufferFactory)
private java.util.Map<java.lang.String,java.lang.Object>	getEncodeHints(ResolvableType actualType, ResolvableType elementType, MediaType mediaType, ServerHttpRequest request, ServerHttpResponse response)
Encoder<?>	getEncoder() Return the configured Encoder, if any.
java.util.List<MediaType>	getWritableMediaTypes() Return the MediaType's that this writer supports.
<any>	write(<any> input, 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.
<any>	write(<any> input, 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.
private void	writeField(java.lang.String fieldName, java.lang.Object fieldValue, java.lang.StringBuilder sb)

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_MEDIA_TYPE

private static final MediaType DEFAULT_MEDIA_TYPE

WRITABLE_MEDIA_TYPES

private static final java.util.List<MediaType> WRITABLE_MEDIA_TYPES

encoder

@Nullable
private final Encoder<?> encoder

Constructor Detail

ServerSentEventHttpMessageWriter

public ServerSentEventHttpMessageWriter()

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

ServerSentEventHttpMessageWriter

public ServerSentEventHttpMessageWriter(@Nullable
                                        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 Detail

getEncoder

@Nullable
public Encoder<?> getEncoder()

Return the configured Encoder, if any.

getWritableMediaTypes

public java.util.List<MediaType> getWritableMediaTypes()

Description copied from interface: HttpMessageWriter

Return the MediaType's that this writer supports.

Specified by:

getWritableMediaTypes in interface HttpMessageWriter<java.lang.Object>

canWrite

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

Description copied from interface: HttpMessageWriter

Write an given stream of object to the output message.

Specified by:

write in interface HttpMessageWriter<java.lang.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

encode

private <any> encode(<any> input,
                     ResolvableType elementType,
                     MediaType mediaType,
                     DataBufferFactory factory,
                     java.util.Map<java.lang.String,java.lang.Object> hints)

writeField

private void writeField(java.lang.String fieldName,
                        java.lang.Object fieldValue,
                        java.lang.StringBuilder sb)

encodeData

private <T> <any> encodeData(@Nullable
                             T dataValue,
                             ResolvableType valueType,
                             MediaType mediaType,
                             DataBufferFactory factory,
                             java.util.Map<java.lang.String,java.lang.Object> hints)

encodeText

private <any> encodeText(java.lang.CharSequence text,
                         MediaType mediaType,
                         DataBufferFactory bufferFactory)

write

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

Description copied from interface: HttpMessageWriter

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

Specified by:

write in interface HttpMessageWriter<java.lang.Object>

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

getEncodeHints

private java.util.Map<java.lang.String,java.lang.Object> getEncodeHints(ResolvableType actualType,
                                                                        ResolvableType elementType,
                                                                        @Nullable
                                                                        MediaType mediaType,
                                                                        ServerHttpRequest request,
                                                                        ServerHttpResponse response)