Polishing

spring-messaging/src/main/java/org/springframework/messaging/simp/broker/OrderedMessageSender.java

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package org.springframework.messaging.simp.broker;
 
 import java.util.Queue;
@@ -21,6 +22,7 @@ import java.util.concurrent.atomic.AtomicBoolean;
 
 import org.apache.commons.logging.Log;
 
+import org.springframework.lang.Nullable;
 import org.springframework.messaging.Message;
 import org.springframework.messaging.MessageChannel;
 import org.springframework.messaging.MessageHandler;
@@ -31,8 +33,8 @@ import org.springframework.messaging.support.MessageHeaderAccessor;
 import org.springframework.util.Assert;
 
 /**
- * Submit messages to an ExecutorSubscribableChannel, one at a time. The channel
- * must have been configured with {@link #configureOutboundChannel}.
+ * Submit messages to an {@link ExecutorSubscribableChannel}, one at a time.
+ * The channel must have been configured with {@link #configureOutboundChannel}.
  *
  * @author Rossen Stoyanchev
  * @since 5.1
@@ -69,7 +71,6 @@ class OrderedMessageSender implements MessageChannel {
 	}
 
 	private void trySend() {
-
 		// Take sendInProgress flag only if queue is not empty
 		if (this.messages.isEmpty()) {
 			return;
@@ -141,7 +142,9 @@ class OrderedMessageSender implements MessageChannel {
 	private static class CallbackInterceptor implements ExecutorChannelInterceptor {
 
 		@Override
-		public void afterMessageHandled(Message<?> msg, MessageChannel ch, MessageHandler handler, Exception ex) {
+		public void afterMessageHandled(
+				Message<?> msg, MessageChannel ch, MessageHandler handler, @Nullable Exception ex) {
+
 			Runnable task = (Runnable) msg.getHeaders().get(OrderedMessageSender.COMPLETION_TASK_HEADER);
 			if (task != null) {
 				task.run();

spring-messaging/src/main/java/org/springframework/messaging/simp/config/MessageBrokerRegistry.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -162,30 +162,6 @@ public class MessageBrokerRegistry {
 		return this.userDestinationPrefix;
 	}
 
-	/**
-	 * Whether the client must receive messages in the order of publication.
-	 * <p>By default messages sent to the {@code "clientOutboundChannel"} may
-	 * not be processed in the same order because the channel is backed by a
-	 * ThreadPoolExecutor that in turn does not guarantee processing in order.
-	 * <p>When this flag is set to {@code true} messages within the same session
-	 * will be sent to the {@code "clientOutboundChannel"} one at a time in
-	 * order to preserve the order of publication. Enable this only if needed
-	 * since there is some performance overhead to keep messages in order.
-	 * @param preservePublishOrder whether to publish in order
-	 * @since 5.1
-	 */
-	public void setPreservePublishOrder(boolean preservePublishOrder) {
-		this.preservePublishOrder = preservePublishOrder;
-	}
-
-	/**
-	 * Whether to ensure messages are received in the order of publication.
-	 * @since 5.1
-	 */
-	protected boolean isPreservePublishOrder() {
-		return this.preservePublishOrder;
-	}
-
 	/**
 	 * Configure the PathMatcher to use to match the destinations of incoming
 	 * messages to {@code @MessageMapping} and {@code @SubscribeMapping} methods.
@@ -225,6 +201,21 @@ public class MessageBrokerRegistry {
 		return this;
 	}
 
+	/**
+	 * Whether the client must receive messages in the order of publication.
+	 * <p>By default messages sent to the {@code "clientOutboundChannel"} may
+	 * not be processed in the same order because the channel is backed by a
+	 * ThreadPoolExecutor that in turn does not guarantee processing in order.
+	 * <p>When this flag is set to {@code true} messages within the same session
+	 * will be sent to the {@code "clientOutboundChannel"} one at a time in
+	 * order to preserve the order of publication. Enable this only if needed
+	 * since there is some performance overhead to keep messages in order.
+	 * @since 5.1
+	 */
+	public MessageBrokerRegistry setPreservePublishOrder(boolean preservePublishOrder) {
+		this.preservePublishOrder = preservePublishOrder;
+		return this;
+	}
 
 	@Nullable
 	protected SimpleBrokerMessageHandler getSimpleBroker(SubscribableChannel brokerChannel) {

spring-messaging/src/main/java/org/springframework/messaging/support/ChannelInterceptor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -28,6 +28,8 @@ import org.springframework.messaging.MessageChannel;
  * @author Mark Fisher
  * @author Rossen Stoyanchev
  * @since 4.0
+ * @see Message
+ * @see MessageChannel
  */
 public interface ChannelInterceptor {
 
@@ -56,8 +58,8 @@ public interface ChannelInterceptor {
 	 * completed and returned a Message, i.e. it did not return {@code null}.
 	 * @since 4.1
 	 */
-	default void afterSendCompletion(Message<?> message, MessageChannel channel, boolean sent,
-			@Nullable Exception ex) {
+	default void afterSendCompletion(
+			Message<?> message, MessageChannel channel, boolean sent, @Nullable Exception ex) {
 	}
 
 	/**

spring-messaging/src/main/java/org/springframework/messaging/support/ExecutorChannelInterceptor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -26,10 +26,13 @@ import org.springframework.messaging.MessageHandler;
  * asynchronous sending of a {@link org.springframework.messaging.Message} to
  * a specific subscriber through an {@link java.util.concurrent.Executor}.
  * Supported on {@link org.springframework.messaging.MessageChannel}
- * implementations that can be configured with an Executor.
+ * implementations that can be configured with an {@code Executor}.
  *
  * @author Rossen Stoyanchev
  * @since 4.1
+ * @see Message
+ * @see MessageChannel
+ * @see MessageHandler
  */
 public interface ExecutorChannelInterceptor extends ChannelInterceptor {