INT-1500: add apply-sequence flag to splitter.

spring-integration-core/src/main/java/org/springframework/integration/config/SplitterFactoryBean.java

@@ -29,6 +29,7 @@ import org.springframework.util.StringUtils;
  * Factory bean for creating a Message Splitter.
  * 
  * @author Mark Fisher
+ * @author Iwein Fuld
  */
 public class SplitterFactoryBean extends AbstractMessageHandlerFactoryBean {
 
@@ -36,6 +37,8 @@ public class SplitterFactoryBean extends AbstractMessageHandlerFactoryBean {
 
 	private volatile boolean requiresReply;
 
+	private volatile boolean applySequence = true;
+
 
 	public void setSendTimeout(Long sendTimeout) {
 		this.sendTimeout = sendTimeout;
@@ -49,6 +52,10 @@ public class SplitterFactoryBean extends AbstractMessageHandlerFactoryBean {
 		this.requiresReply = requiresReply;
 	}
 
+	public void setApplySequence(boolean applySequence) {
+		this.applySequence = applySequence;
+	}
+
 	@Override
 	MessageHandler createMethodInvokingHandler(Object targetObject, String targetMethodName) {
 		Assert.notNull(targetObject, "targetObject must not be null");
@@ -89,6 +96,7 @@ public class SplitterFactoryBean extends AbstractMessageHandlerFactoryBean {
 			splitter.setSendTimeout(sendTimeout);
 		}
 		splitter.setRequiresReply(requiresReply);
+		splitter.setApplySequence(applySequence);
 		return splitter;
 	}
 

spring-integration-core/src/main/java/org/springframework/integration/config/xml/SplitterParser.java

@@ -16,10 +16,15 @@
 
 package org.springframework.integration.config.xml;
 
+import org.springframework.beans.factory.support.BeanDefinitionBuilder;
+import org.springframework.beans.factory.xml.ParserContext;
+import org.w3c.dom.Element;
+
 /**
  * Parser for the <splitter/> element.
  * 
  * @author Mark Fisher
+ * @author Iwein Fuld
  */
 public class SplitterParser extends AbstractDelegatingConsumerEndpointParser {
 
@@ -33,4 +38,8 @@ public class SplitterParser extends AbstractDelegatingConsumerEndpointParser {
 		return true;
 	}
 
+	@Override
+	void postProcess(BeanDefinitionBuilder builder, Element element, ParserContext parserContext) {
+		IntegrationNamespaceUtils.setValueIfAttributeDefined(builder, element, "apply-sequence");
+	}
 }

spring-integration-core/src/main/java/org/springframework/integration/splitter/AbstractMessageSplitter.java

@@ -35,6 +35,15 @@ import org.springframework.util.ObjectUtils;
  */
 public abstract class AbstractMessageSplitter extends AbstractReplyProducingMessageHandler {
 
+	private boolean applySequence = true;
+
+	/**
+	 * Set the applySequence flag to the specified value. Defaults to true.
+	 */
+	public void setApplySequence(boolean applySequence) {
+		this.applySequence = applySequence;
+	}
+
 	@Override
 	@SuppressWarnings("unchecked")
 	protected final Object handleRequestMessage(Message<?> message) {
@@ -80,7 +89,9 @@ public abstract class AbstractMessageSplitter extends AbstractReplyProducingMess
 			builder = MessageBuilder.withPayload(item);
 			builder.copyHeaders(headers);
 		}
-		builder.pushSequenceDetails(correlationId, sequenceNumber, sequenceSize);
+		if (this.applySequence) {
+			builder.pushSequenceDetails(correlationId, sequenceNumber, sequenceSize);
+		}
 		return builder;
 	}
 

spring-integration-core/src/main/resources/org/springframework/integration/config/xml/spring-integration-2.0.xsd

@@ -2118,6 +2118,15 @@ Name of the header whose value to use.
 							</xsd:documentation>
 						</xsd:annotation>
 					</xsd:attribute>
+					<xsd:attribute name="apply-sequence" type="xsd:boolean" use="optional">
+						<xsd:annotation>
+							<xsd:documentation>
+	Set this flag to false to prevent adding sequence related headers in this splitter. This
+	can be convenient in cases where the set sequence numbers conflict with downstream custom
+	aggregations.
+							</xsd:documentation>
+						</xsd:annotation>
+					</xsd:attribute>
 				</xsd:extension>
 			</xsd:complexContent>
 		</xsd:complexType>

spring-integration-core/src/test/java/org/springframework/integration/router/config/SplitterParserTests.java

@@ -16,25 +16,24 @@
 
 package org.springframework.integration.router.config;
 
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNull;
-
-import java.util.Collections;
-
 import org.junit.Test;
-
 import org.springframework.context.support.ClassPathXmlApplicationContext;
 import org.springframework.integration.Message;
 import org.springframework.integration.MessageChannel;
 import org.springframework.integration.MessageHandlingException;
 import org.springframework.integration.channel.DirectChannel;
 import org.springframework.integration.core.PollableChannel;
-import org.springframework.integration.endpoint.EventDrivenConsumer;
 import org.springframework.integration.message.GenericMessage;
 import org.springframework.integration.support.MessageBuilder;
 
+import java.util.Collections;
+
+import static org.hamcrest.Matchers.is;
+import static org.junit.Assert.*;
+
 /**
  * @author Mark Fisher
+ * @author Iwein Fuld
  */
 public class SplitterParserTests {
 
@@ -104,4 +103,18 @@ public class SplitterParserTests {
 		inputChannel.send(MessageBuilder.withPayload(Collections.emptyList()).build());
 	}
 
+	@Test
+	public void splitterParserTestApplySequenceFalse() {
+		ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(
+				"splitterParserTests.xml", this.getClass());
+		context.start();
+		DirectChannel inputChannel = context.getBean("noSequenceInput", DirectChannel.class);
+		PollableChannel output = (PollableChannel) context.getBean("output");
+		inputChannel.send(MessageBuilder.withPayload(Collections.emptyList()).build());
+		Message<?> message = output.receive(1000);
+		assertThat(message.getHeaders().getSequenceNumber(), is(0));
+		assertThat(message.getHeaders().getSequenceSize(), is(0));
+	}
+
+
 }

spring-integration-core/src/test/java/org/springframework/integration/router/config/splitterParserTests.xml

@@ -32,6 +32,13 @@
 	          output-channel="output" 
 	          requires-reply="true"/>
 
+	<splitter id="splitterBeanNoSequence"
+			  ref="splitterBean"
+	          input-channel="noSequenceInput"
+	          output-channel="output"
+			  apply-sequence="false"
+	  />
+
 	<beans:bean id="splitterBean" class="org.springframework.integration.router.config.TestSplitterBean"/>
 
 	<beans:bean id="splitterImpl" class="org.springframework.integration.router.config.TestSplitterImpl"/>