GH-1474: Fix MessageProperties.lastInBatch

Resolves #1474

When consuming the whole debatched batch as a list, all messages
had the `lastInBatch` property set to true.

Clone the message properties for the last record.

**cherry-pick to 2.4.x**

spring-amqp/src/main/java/org/springframework/amqp/core/MessageProperties.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2022 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.
@@ -140,6 +140,15 @@ public void setHeader(String key, Object value) {
 		this.headers.put(key, value);
 	}
 
+	/**
+	 * Set headers.
+	 * @param headers the headers.
+	 * @since 2.4.7
+	 */
+	public void setHeaders(Map<String, Object> headers) {
+		this.headers.putAll(headers);
+	}
+
 	/**
 	 * Typed getter for a header.
 	 * @param headerName the header name.

spring-rabbit/src/main/java/org/springframework/amqp/rabbit/batch/SimpleBatchingStrategy.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2019 the original author or authors.
+ * Copyright 2014-2022 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.
@@ -29,6 +29,7 @@
 import org.springframework.amqp.rabbit.support.ListenerExecutionFailedException;
 import org.springframework.amqp.support.AmqpHeaders;
 import org.springframework.amqp.support.converter.MessageConversionException;
+import org.springframework.beans.BeanUtils;
 import org.springframework.util.Assert;
 
 /**
@@ -184,10 +185,16 @@ public void deBatch(Message message, Consumer<Message> fragmentConsumer) {
 			byte[] body = new byte[length];
 			byteBuffer.get(body);
 			messageProperties.setContentLength(length);
-			// Caveat - shared MessageProperties.
-			Message fragment = new Message(body, messageProperties);
-			if (!byteBuffer.hasRemaining()) {
-				messageProperties.setLastInBatch(true);
+			// Caveat - shared MessageProperties, except for last
+			Message fragment;
+			if (byteBuffer.hasRemaining()) {
+				 fragment = new Message(body, messageProperties);
+			}
+			else {
+				MessageProperties lastProperties = new MessageProperties();
+				BeanUtils.copyProperties(messageProperties, lastProperties);
+				lastProperties.setLastInBatch(true);
+				fragment = new Message(body, lastProperties);
 			}
 			fragmentConsumer.accept(fragment);
 		}

spring-rabbit/src/test/java/org/springframework/amqp/rabbit/core/BatchingRabbitTemplateTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2020 the original author or authors.
+  * Copyright 2014-2022 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.
@@ -261,8 +261,8 @@ private void testDebatchByContainer(AbstractMessageListenerContainer container,
 		if (asList) {
 			container.setMessageListener((BatchMessageListener) messages -> {
 				received.addAll(messages);
-				lastInBatch.add(false);
-				lastInBatch.add(true);
+				lastInBatch.add(messages.get(0).getMessageProperties().isLastInBatch());
+				lastInBatch.add(messages.get(1).getMessageProperties().isLastInBatch());
 				batchSize.set(messages.size());
 				latch.countDown();
 			});