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

Class SseEmitter

java.lang.Object
org.springframework.web.servlet.mvc.method.annotation.ResponseBodyEmitter
org.springframework.web.servlet.mvc.method.annotation.SseEmitter
public class SseEmitter extends ResponseBodyEmitter
A specialization of ResponseBodyEmitter for sending Server-Sent Events.
Since:
4.2
Author:
Rossen Stoyanchev, Juergen Hoeller, Sam Brannen, Brian Clozel

  • Constructor Details

    • SseEmitter

      public SseEmitter()
      Create a new SseEmitter instance.

    • SseEmitter

      public SseEmitter(Long timeout)
      Create a SseEmitter with a custom timeout value.

      By default not set in which case the default configured in the MVC Java Config or the MVC namespace is used, or if that's not set, then the timeout depends on the default of the underlying server.

      Parameters:
      timeout - the timeout value in milliseconds
      Since:
      4.2.2

  • Method Details

    • extendResponse

      protected void extendResponse(ServerHttpResponse outputMessage)
      Description copied from class: ResponseBodyEmitter
      Invoked after the response is updated with the status code and headers, if the ResponseBodyEmitter is wrapped in a ResponseEntity, but before the response is committed, i.e. before the response body has been written to.

      The default implementation is empty.

      Overrides:
      extendResponse in class ResponseBodyEmitter

    • send

      public void send(Object object) throws IOException
      Send the object formatted as a single SSE "data" line. It's equivalent to: 
       // static import of SseEmitter.*

 SseEmitter emitter = new SseEmitter();
 emitter.send(event().data(myObject));

      Please, see parent Javadoc for important notes on exception handling.

      Overrides:
      send in class ResponseBodyEmitter
      Parameters:
      object - the object to write
      Throws:
      IOException - raised when an I/O error occurs
      IllegalStateException - wraps any other errors

    • send

      public void send(Object object, @Nullable MediaType mediaType) throws IOException
      Send the object formatted as a single SSE "data" line. It's equivalent to: 
       // static import of SseEmitter.*

 SseEmitter emitter = new SseEmitter();
 emitter.send(event().data(myObject, MediaType.APPLICATION_JSON));

      Please, see parent Javadoc for important notes on exception handling.

      Overrides:
      send in class ResponseBodyEmitter
      Parameters:
      object - the object to write
      mediaType - a MediaType hint for selecting an HttpMessageConverter
      Throws:
      IOException - raised when an I/O error occurs

    • send

      public void send(SseEmitter.SseEventBuilder builder) throws IOException
      Send an SSE event prepared with the given builder. For example: 
       // static import of SseEmitter
 SseEmitter emitter = new SseEmitter();
 emitter.send(event().name("update").id("1").data(myObject));
      Parameters:
      builder - a builder for an SSE formatted event.
      Throws:
      IOException - raised when an I/O error occurs

    • toString

      public String toString()
      Overrides:
      toString in class ResponseBodyEmitter

    • event

      public static SseEmitter.SseEventBuilder event()