Refactored SseEvent to ServerSentEvent

- Renamed SseEvent to ServerSentEvent to make the name less redundant.
 - ServerSentEvent is now immutable, having a builder to create new instances.
 - Realigned the class properties to more closely match the events
   described in the spec, so that `reconnectTime` becomes `retry`, and
   `name` becomes `event`.

spring-web-reactive/src/main/java/org/springframework/web/reactive/config/WebReactiveConfiguration.java

@@ -44,7 +44,7 @@ import org.springframework.http.codec.EncoderHttpMessageWriter;
 import org.springframework.http.codec.HttpMessageReader;
 import org.springframework.http.codec.HttpMessageWriter;
 import org.springframework.http.codec.ResourceHttpMessageWriter;
-import org.springframework.http.codec.SseEventHttpMessageWriter;
+import org.springframework.http.codec.ServerSentEventHttpMessageWriter;
 import org.springframework.http.codec.json.Jackson2JsonDecoder;
 import org.springframework.http.codec.json.Jackson2JsonEncoder;
 import org.springframework.http.codec.xml.Jaxb2XmlDecoder;
@@ -372,7 +372,7 @@ public class WebReactiveConfiguration implements ApplicationContextAware {
 			writers.add(new EncoderHttpMessageWriter<>(jacksonEncoder));
 			sseDataEncoders.add(jacksonEncoder);
 		}
-		writers.add(new SseEventHttpMessageWriter(sseDataEncoders));
+		writers.add(new ServerSentEventHttpMessageWriter(sseDataEncoders));
 	}
 	/**
 	 * Override this to modify the list of message writers after it has been

spring-web-reactive/src/test/java/org/springframework/web/reactive/result/method/annotation/SseIntegrationTests.java

@@ -28,7 +28,7 @@ import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.http.MediaType;
 import org.springframework.http.client.reactive.ReactorClientHttpConnector;
-import org.springframework.http.codec.SseEvent;
+import org.springframework.http.codec.ServerSentEvent;
 import org.springframework.http.server.reactive.AbstractHttpHandlerIntegrationTests;
 import org.springframework.http.server.reactive.HttpHandler;
 import org.springframework.tests.TestSubscriber;
@@ -135,14 +135,11 @@ public class SseIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 		}
 
 		@RequestMapping("/sse/event")
-		Flux<SseEvent> sse() {
-			return Flux.interval(Duration.ofMillis(100)).map(l -> {
-				SseEvent event = new SseEvent();
-				event.setId(Long.toString(l));
-				event.setData("foo");
-				event.setComment("bar");
-				return event;
-			}).take(2);
+		Flux<ServerSentEvent<String>> sse() {
+			return Flux.interval(Duration.ofMillis(100)).map(l -> ServerSentEvent.builder("foo")
+					.id(Long.toString(l))
+					.comment("bar")
+					.build()).take(2);
 		}
 
 	}

spring-web/src/main/java/org/springframework/http/codec/ServerSentEvent.java

@@ -0,0 +1,226 @@
+/*
+ * Copyright 2002-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.http.codec;
+
+import java.time.Duration;
+import java.util.Optional;
+
+import org.springframework.http.codec.json.Jackson2JsonEncoder;
+
+/**
+ * Representation for a Server-Sent Event for use with Spring's reactive Web
+ * support. {@code Flux<SseEvent>} or {@code Observable<SseEvent>} is the
+ * reactive equivalent to Spring MVC's {@code SseEmitter}.
+ *
+ * @param <T> the type of data that this event contains
+ * @author Sebastien Deleuze
+ * @author Arjen Poutsma
+ * @see ServerSentEventHttpMessageWriter
+ * @see <a href="https://www.w3.org/TR/eventsource/">Server-Sent Events W3C recommendation</a>
+ * @since 5.0
+ */
+public class ServerSentEvent<T> {
+
+    private final String id;
+
+    private final String event;
+
+    private final T data;
+
+    private final Duration retry;
+
+    private final String comment;
+
+    private ServerSentEvent(String id, String event, T data, Duration retry, String comment) {
+        this.id = id;
+        this.event = event;
+        this.data = data;
+        this.retry = retry;
+        this.comment = comment;
+    }
+
+    /**
+     * Return a builder for a {@code SseEvent}.
+     *
+     * @param <T> the type of data that this event contains
+     * @return the builder
+     */
+    public static <T> Builder<T> builder() {
+        return new BuilderImpl<>();
+    }
+
+    /**
+     * Return a builder for a {@code SseEvent}, populated with the give {@linkplain #data() data}.
+     *
+     * @param <T> the type of data that this event contains
+     * @return the builder
+     */
+    public static <T> Builder<T> builder(T data) {
+        return new BuilderImpl<>(data);
+    }
+
+    /**
+     * Return the {@code id} field of this event, if available.
+     */
+    public Optional<String> id() {
+        return Optional.ofNullable(this.id);
+    }
+
+    /**
+     * Return the {@code event} field of this event, if available.
+     */
+    public Optional<String> event() {
+        return Optional.ofNullable(this.event);
+    }
+
+    /**
+     * Return the {@code data} field of this event, if available.
+     */
+    public Optional<T> data() {
+        return Optional.ofNullable(this.data);
+    }
+
+    /**
+     * Return the {@code retry} field of this event, if available.
+     */
+    public Optional<Duration> retry() {
+        return Optional.ofNullable(this.retry);
+    }
+
+    /**
+     * Return the comment of this event, if available.
+     */
+    public Optional<String> comment() {
+        return Optional.ofNullable(this.comment);
+    }
+
+    /**
+     * A mutable builder for a {@code SseEvent}.
+     *
+     * @param <T> the type of data that this event contains
+     */
+    public interface Builder<T> {
+
+        /**
+         * Set the value of the {@code id} field.
+         *
+         * @param id the value of the id field
+         * @return {@code this} builder
+         */
+        Builder<T> id(String id);
+
+        /**
+         * Set the value of the {@code event} field.
+         *
+         * @param event the value of the event field
+         * @return {@code this} builder
+         */
+        Builder<T> event(String event);
+
+        /**
+         * Set the value of the {@code data} field. If the {@code data} argument is a multi-line {@code String}, it
+         * will be turned into multiple {@code data} field lines as defined in Server-Sent Events
+         * W3C recommendation. If {@code data} is not a String, it will be
+         * {@linkplain Jackson2JsonEncoder encoded} into JSON.
+         *
+         * @param data the value of the data field
+         * @return {@code this} builder
+         */
+        Builder<T> data(T data);
+
+        /**
+         * Set the value of the {@code retry} field.
+         *
+         * @param retry the value of the retry field
+         * @return {@code this} builder
+         */
+        Builder<T> retry(Duration retry);
+
+        /**
+         * Set SSE comment. If a multi-line comment is provided, it will be turned into multiple
+         * SSE comment lines as defined in Server-Sent Events W3C
+         * recommendation.
+         *
+         * @param comment the comment to set
+         * @return {@code this} builder
+         */
+        Builder<T> comment(String comment);
+
+        /**
+         * Builds the event.
+         *
+         * @return the built event
+         */
+        ServerSentEvent<T> build();
+    }
+
+    private static class BuilderImpl<T> implements Builder<T> {
+
+        private T data;
+
+        private String id;
+
+        private String event;
+
+        private Duration retry;
+
+        private String comment;
+
+	    public BuilderImpl() {
+	    }
+
+	    public BuilderImpl(T data) {
+		    this.data = data;
+	    }
+
+	    @Override
+        public Builder<T> id(String id) {
+            this.id = id;
+            return this;
+        }
+
+        @Override
+        public Builder<T> event(String event) {
+            this.event = event;
+            return this;
+        }
+
+        @Override
+        public Builder<T> data(T data) {
+            this.data = data;
+            return this;
+        }
+
+        @Override
+        public Builder<T> retry(Duration retry) {
+            this.retry = retry;
+            return this;
+        }
+
+        @Override
+        public Builder<T> comment(String comment) {
+            this.comment = comment;
+            return this;
+        }
+
+        @Override
+        public ServerSentEvent<T> build() {
+            return new ServerSentEvent<T>(this.id, this.event, this.data, this.retry, this.comment);
+        }
+    }
+
+}

spring-web/src/main/java/org/springframework/http/codec/ServerSentEventHttpMessageWriter.java

@@ -33,24 +33,29 @@ import org.springframework.core.io.buffer.DataBufferFactory;
 import org.springframework.http.MediaType;
 import org.springframework.http.ReactiveHttpOutputMessage;
 import org.springframework.util.Assert;
+import org.springframework.util.MimeTypeUtils;
 
 /**
- * Encoder that supports a stream of {@link SseEvent}s and also plain
- * {@link Object}s which is the same as an {@link SseEvent} with data
+ * Encoder that supports a stream of {@link ServerSentEvent}s and also plain
+ * {@link Object}s which is the same as an {@link ServerSentEvent} with data
  * only.
  *
  * @author Sebastien Deleuze
- * @since 5.0
  * @author Arjen Poutsma
+ * @since 5.0
  */
-public class SseEventHttpMessageWriter implements HttpMessageWriter<Object> {
+public class ServerSentEventHttpMessageWriter implements HttpMessageWriter<Object> {
 
 	private static final MediaType TEXT_EVENT_STREAM =
 			new MediaType("text", "event-stream");
 
 	private final List<Encoder<?>> dataEncoders;
 
-	public SseEventHttpMessageWriter(List<Encoder<?>> dataEncoders) {
+	public ServerSentEventHttpMessageWriter() {
+		this.dataEncoders = Collections.emptyList();
+	}
+
+	public ServerSentEventHttpMessageWriter(List<Encoder<?>> dataEncoders) {
 		Assert.notNull(dataEncoders, "'dataEncoders' must not be null");
 		this.dataEncoders = dataEncoders;
 	}
@@ -67,7 +72,7 @@ public class SseEventHttpMessageWriter implements HttpMessageWriter<Object> {
 
 	@Override
 	public Mono<Void> write(Publisher<?> inputStream, ResolvableType type,
-			MediaType contentType, ReactiveHttpOutputMessage outputMessage) {
+							MediaType contentType, ReactiveHttpOutputMessage outputMessage) {
 
 		outputMessage.getHeaders().setContentType(TEXT_EVENT_STREAM);
 
@@ -82,68 +87,60 @@ public class SseEventHttpMessageWriter implements HttpMessageWriter<Object> {
 	}
 
 	private Flux<Publisher<DataBuffer>> encode(Publisher<?> inputStream,
-			DataBufferFactory bufferFactory, ResolvableType type) {
+											   DataBufferFactory bufferFactory, ResolvableType type) {
 
-		return Flux.from(inputStream).map(input -> {
-			SseEvent event =
-					(SseEvent.class.equals(type.getRawClass()) ? (SseEvent) input :
-							new SseEvent(input));
+		return Flux.from(inputStream)
+				.map(o -> toSseEvent(o, type))
+				.map(sse -> {
+					StringBuilder sb = new StringBuilder();
+					sse.id().ifPresent(id -> writeField("id", id, sb));
+					sse.event().ifPresent(event -> writeField("event", event, sb));
+					sse.retry().ifPresent(retry -> writeField("retry", retry.toMillis(), sb));
+					sse.comment().ifPresent(comment -> {
+						comment = comment.replaceAll("\\n", "\n:");
+						sb.append(':').append(comment).append("\n");
+					});
+					Flux<DataBuffer> dataBuffer = sse.data()
+							.<Flux<DataBuffer>>map(data -> {
+								sb.append("data:");
+								if (data instanceof String) {
+									String stringData = ((String) data).replaceAll("\\n", "\ndata:");
+									sb.append(stringData).append('\n');
+									return Flux.empty();
+								}
+								else {
+									return applyEncoder(data, bufferFactory);
+								}
+							}).orElse(Flux.empty());
 
-			StringBuilder sb = new StringBuilder();
-
-			if (event.getId() != null) {
-				sb.append("id:");
-				sb.append(event.getId());
-				sb.append("\n");
-			}
-
-			if (event.getName() != null) {
-				sb.append("event:");
-				sb.append(event.getName());
-				sb.append("\n");
-			}
-
-			if (event.getReconnectTime() != null) {
-				sb.append("retry:");
-				sb.append(event.getReconnectTime().toString());
-				sb.append("\n");
-			}
-
-			if (event.getComment() != null) {
-				sb.append(":");
-				sb.append(event.getComment().replaceAll("\\n", "\n:"));
-				sb.append("\n");
-			}
-
-			Object data = event.getData();
-			Flux<DataBuffer> dataBuffer = Flux.empty();
-			MediaType mediaType =
-					(event.getMediaType() == null ? MediaType.ALL : event.getMediaType());
-			if (data != null) {
-				sb.append("data:");
-				if (data instanceof String) {
-					sb.append(((String) data).replaceAll("\\n", "\ndata:")).append("\n");
-				}
-				else {
-					dataBuffer = applyEncoder(data, mediaType, bufferFactory);
-				}
-			}
-
-			return Flux.concat(encodeString(sb.toString(), bufferFactory), dataBuffer,
-					encodeString("\n", bufferFactory));
-		});
+					return Flux.concat(encodeString(sb.toString(), bufferFactory), dataBuffer,
+							encodeString("\n", bufferFactory));
+				});
 
 	}
 
+	private ServerSentEvent<?> toSseEvent(Object data, ResolvableType type) {
+		return ServerSentEvent.class.isAssignableFrom(type.getRawClass())
+				? (ServerSentEvent<?>) data
+				: ServerSentEvent.builder().data(data).build();
+	}
+
+	private void writeField(String fieldName, Object fieldValue, StringBuilder stringBuilder) {
+		stringBuilder.append(fieldName);
+		stringBuilder.append(':');
+		stringBuilder.append(fieldValue.toString());
+		stringBuilder.append("\n");
+	}
+
 	@SuppressWarnings("unchecked")
-	private <T> Flux<DataBuffer> applyEncoder(Object data, MediaType mediaType, DataBufferFactory bufferFactory) {
+	private <T> Flux<DataBuffer> applyEncoder(Object data, DataBufferFactory bufferFactory) {
 		ResolvableType elementType = ResolvableType.forClass(data.getClass());
 		Optional<Encoder<?>> encoder = dataEncoders
-			.stream()
-			.filter(e -> e.canEncode(elementType, mediaType))
-			.findFirst();
+				.stream()
+				.filter(e -> e.canEncode(elementType, MimeTypeUtils.APPLICATION_JSON))
+				.findFirst();
 		return ((Encoder<T>) encoder.orElseThrow(() -> new CodecException("No suitable encoder found!")))
-				.encode(Mono.just((T) data), bufferFactory, elementType, mediaType)
+				.encode(Mono.just((T) data), bufferFactory, elementType, MimeTypeUtils.APPLICATION_JSON)
 				.concatWith(encodeString("\n", bufferFactory));
 	}
 

spring-web/src/main/java/org/springframework/http/codec/SseEvent.java

@@ -1,165 +0,0 @@
-/*
- * Copyright 2002-2016 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.springframework.http.codec;
-
-import org.springframework.http.MediaType;
-
-/**
- * Representation for a Server-Sent Event for use with Spring's reactive Web
- * support. {@code Flux<SseEvent>} or {@code Observable<SseEvent>} is the
- * reactive equivalent to Spring MVC's {@code SseEmitter}.
- *
- * @author Sebastien Deleuze
- * @since 5.0
- * @see SseEventHttpMessageWriter
- * @see <a href="https://www.w3.org/TR/eventsource/">Server-Sent Events W3C recommendation</a>
- */
-public class SseEvent {
-
-	private String id;
-
-	private String name;
-
-	private Object data;
-
-	private MediaType mediaType;
-
-	private Long reconnectTime;
-
-	private String comment;
-
-
-	/**
-	 * Create an empty instance.
-	 */
-	public SseEvent() {
-	}
-
-	/**
-	 * Create an instance with the provided {@code data}.
-	 */
-	public SseEvent(Object data) {
-		this.data = data;
-	}
-
-	/**
-	 * Create an instance with the provided {@code data} and {@code mediaType}.
-	 */
-	public SseEvent(Object data, MediaType mediaType) {
-		this.data = data;
-		this.mediaType = mediaType;
-	}
-
-
-	/**
-	 * Set the {@code id} SSE field
-	 */
-	public void setId(String id) {
-		this.id = id;
-	}
-
-	/**
-	 * @see #setId(String)
-	 */
-	public String getId() {
-		return id;
-	}
-
-	/**
-	 * Set the {@code event} SSE field
-	 */
-	public void setName(String name) {
-		this.name = name;
-	}
-
-	/**
-	 * @see #setName(String)
-	 */
-	public String getName() {
-		return name;
-	}
-
-	/**
-	 * Set {@code data} SSE field. If a multiline {@code String} is provided, it will be
-	 * turned into multiple {@code data} field lines as defined in Server-Sent Events
-	 * W3C recommendation.
-	 *
-	 * If no {@code mediaType} is defined, default {@link SseEventHttpMessageWriter} will:
-	 *  - Turn single line {@code String} to a single {@code data} field
-	 *  - Turn multiline line {@code String} to multiple {@code data} fields
-	 *  - Serialize other {@code Object} as JSON
-	 *
-	 * @see #setMediaType(MediaType)
-	 */
-	public void setData(Object data) {
-		this.data = data;
-	}
-
-	/**
-	 * @see #setData(Object)
-	 */
-	public Object getData() {
-		return data;
-	}
-
-	/**
-	 * Set the {@link MediaType} used to serialize the {@code data}.
-	 * {@link SseEventHttpMessageWriter} should be configured with the relevant encoder to be
-	 * able to serialize it.
-	 */
-	public void setMediaType(MediaType mediaType) {
-		this.mediaType = mediaType;
-	}
-
-	/**
-	 * @see #setMediaType(MediaType)
-	 */
-	public MediaType getMediaType() {
-		return this.mediaType;
-	}
-
-	/**
-	 * Set the {@code retry} SSE field
-	 */
-	public void setReconnectTime(Long reconnectTime) {
-		this.reconnectTime = reconnectTime;
-	}
-
-	/**
-	 * @see #setReconnectTime(Long)
-	 */
-	public Long getReconnectTime() {
-		return reconnectTime;
-	}
-
-	/**
-	 * Set SSE comment. If a multiline comment is provided, it will be turned into multiple
-	 * SSE comment lines by {@link SseEventHttpMessageWriter} as defined in Server-Sent Events W3C
-	 * recommendation.
-	 */
-	public void setComment(String comment) {
-		this.comment = comment;
-	}
-
-	/**
-	 * @see #setComment(String)
-	 */
-	public String getComment() {
-		return comment;
-	}
-
-}

spring-web/src/test/java/org/springframework/http/codec/ServerSentEventHttpMessageWriterTests.java

@@ -16,6 +16,7 @@
 
 package org.springframework.http.codec;
 
+import java.time.Duration;
 import java.util.Collections;
 
 import org.junit.Test;
@@ -31,44 +32,43 @@ import org.springframework.http.codec.json.Jackson2JsonEncoder;
 import org.springframework.http.server.reactive.MockServerHttpResponse;
 import org.springframework.tests.TestSubscriber;
 
-import static org.junit.Assert.*;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
 
 /**
  * @author Sebastien Deleuze
  */
-public class SseEventHttpMessageWriterTests extends AbstractDataBufferAllocatingTestCase {
+public class ServerSentEventHttpMessageWriterTests extends AbstractDataBufferAllocatingTestCase {
 
-	private SseEventHttpMessageWriter converter = new SseEventHttpMessageWriter(
+	private ServerSentEventHttpMessageWriter messageWriter = new ServerSentEventHttpMessageWriter(
 			Collections.singletonList(new Jackson2JsonEncoder()));
 
 
 	@Test
 	public void nullMimeType() {
-		assertTrue(converter.canWrite(ResolvableType.forClass(Object.class), null));
+		assertTrue(messageWriter.canWrite(ResolvableType.forClass(Object.class), null));
 	}
 
 	@Test
 	public void unsupportedMimeType() {
-		assertFalse(converter.canWrite(ResolvableType.forClass(Object.class),
+		assertFalse(messageWriter.canWrite(ResolvableType.forClass(Object.class),
 				new MediaType("foo", "bar")));
 	}
 
 	@Test
 	public void supportedMimeType() {
-		assertTrue(converter.canWrite(ResolvableType.forClass(Object.class),
+		assertTrue(messageWriter.canWrite(ResolvableType.forClass(Object.class),
 				new MediaType("text", "event-stream")));
 	}
 
 	@Test
 	public void encodeServerSentEvent() {
-		SseEvent event = new SseEvent();
-		event.setId("c42");
-		event.setName("foo");
-		event.setComment("bla\nbla bla\nbla bla bla");
-		event.setReconnectTime(123L);
-		Mono<SseEvent> source = Mono.just(event);
+		ServerSentEvent<String>
+				event = ServerSentEvent.<String>builder().data("bar").id("c42").event("foo").comment("bla\nbla bla\nbla bla bla")
+				.retry(Duration.ofMillis(123L)).build();
+		Mono<ServerSentEvent<String>> source = Mono.just(event);
 		MockServerHttpResponse outputMessage = new MockServerHttpResponse();
-		converter.write(source, ResolvableType.forClass(SseEvent.class),
+		messageWriter.write(source, ResolvableType.forClass(ServerSentEvent.class),
 				new MediaType("text", "event-stream"), outputMessage);
 
 		Publisher<Publisher<DataBuffer>> result = outputMessage.getBodyWithFlush();
@@ -77,7 +77,8 @@ public class SseEventHttpMessageWriterTests extends AbstractDataBufferAllocating
 				assertValuesWith(publisher -> {
 					TestSubscriber.subscribe(publisher).assertNoError().assertValuesWith(
 							stringConsumer("id:c42\n" + "event:foo\n" + "retry:123\n" +
-									":bla\n:bla bla\n:bla bla bla\n"),
+									":bla\n:bla bla\n:bla bla bla\n" +
+									"data:bar\n"),
 							stringConsumer("\n"));
 
 				});
@@ -87,7 +88,7 @@ public class SseEventHttpMessageWriterTests extends AbstractDataBufferAllocating
 	public void encodeString() {
 		Flux<String> source = Flux.just("foo", "bar");
 		MockServerHttpResponse outputMessage = new MockServerHttpResponse();
-		converter.write(source, ResolvableType.forClass(String.class),
+		messageWriter.write(source, ResolvableType.forClass(String.class),
 				new MediaType("text", "event-stream"), outputMessage);
 
 		Publisher<Publisher<DataBuffer>> result = outputMessage.getBodyWithFlush();
@@ -110,7 +111,7 @@ public class SseEventHttpMessageWriterTests extends AbstractDataBufferAllocating
 	public void encodeMultiLineString() {
 		Flux<String> source = Flux.just("foo\nbar", "foo\nbaz");
 		MockServerHttpResponse outputMessage = new MockServerHttpResponse();
-		converter.write(source, ResolvableType.forClass(String.class),
+		messageWriter.write(source, ResolvableType.forClass(String.class),
 				new MediaType("text", "event-stream"), outputMessage);
 
 		Publisher<Publisher<DataBuffer>> result = outputMessage.getBodyWithFlush();
@@ -134,7 +135,7 @@ public class SseEventHttpMessageWriterTests extends AbstractDataBufferAllocating
 		Flux<Pojo> source = Flux.just(new Pojo("foofoo", "barbar"),
 				new Pojo("foofoofoo", "barbarbar"));
 		MockServerHttpResponse outputMessage = new MockServerHttpResponse();
-		converter.write(source, ResolvableType.forClass(Pojo.class),
+		messageWriter.write(source, ResolvableType.forClass(Pojo.class),
 				new MediaType("text", "event-stream"), outputMessage);
 
 		Publisher<Publisher<DataBuffer>> result = outputMessage.getBodyWithFlush();