tested optional response flows

src/main/java/org/springframework/integration/flow/config/FlowMessageHandlerFactoryBean.java

@@ -97,8 +97,7 @@ public class FlowMessageHandlerFactoryBean extends AbstractSimpleMessageHandlerF
            this.flowConfiguration = this.flow.getFlowConfiguration().getConfigurationForInputPort(
                 this.inputPortName);
         }
-        Assert.notEmpty(this.flowConfiguration.getOutputPortNames(), "flow [" + this.flow.getBeanName()
-                + "] has no configured output ports");
+ 
         
    
         bridgeMessagingPorts();

src/test/java/org/springframework/integration/flow/FlowUtilsTest.java

@@ -12,11 +12,14 @@ import org.springframework.integration.core.PollableChannel;
 import org.springframework.integration.core.SubscribableChannel;
 import org.springframework.integration.flow.config.FlowUtils;
 import org.springframework.integration.message.GenericMessage;
-
+/**
+ * 
+ * @author David Turanski
+ *
+ */
 public class FlowUtilsTest {
     @Test
     public void buildBridge(){
-        
          
         SubscribableChannel inputChannel = new DirectChannel();
         SubscribableChannel outputChannel = new PublishSubscribeChannel();

src/test/java/org/springframework/integration/flow/config/xml/FlowWithOptionalResponseTest.java

@@ -0,0 +1,61 @@
+package org.springframework.integration.flow.config.xml;
+ 
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Qualifier;
+import org.springframework.integration.Message;
+import org.springframework.integration.MessageChannel;
+import org.springframework.integration.MessagingException;
+import org.springframework.integration.core.MessageHandler;
+import org.springframework.integration.core.SubscribableChannel;
+import org.springframework.integration.message.GenericMessage;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration("classpath:/FlowWithOptionalResponseTest-context.xml")
+public class FlowWithOptionalResponseTest {
+    @Autowired 
+    @Qualifier("inputC")
+    MessageChannel input;
+    
+    @Autowired 
+    @Qualifier("inputCO")
+    MessageChannel inputForOptionalResponse;
+    
+    @Autowired
+    @Qualifier("outputC")
+    SubscribableChannel output;
+    
+    @Test
+    public void testOneWay() {
+    
+        input.send(new GenericMessage<String>("hello"));
+    }
+    
+    @Test
+    public void testOptionResponse() {
+        TestMessageHandler counter = new TestMessageHandler();
+        
+        output.subscribe(counter);
+        
+        for (int i=0; i< 100; i++){
+            inputForOptionalResponse.send(new GenericMessage<String>("hello"));
+        }
+        
+        assertTrue(String.valueOf(counter.count), counter.count >1 && counter.count < 100);    
+    }
+    
+    static class TestMessageHandler implements MessageHandler {
+        int count = 0;
+        @Override
+        public void handleMessage(Message<?> message) throws MessagingException {
+            count++;   
+        }
+    }
+
+    
+}

src/test/resources/FlowWithOptionalResponseTest-context.xml

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<beans xmlns="http://www.springframework.org/schema/beans"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xmlns:int="http://www.springframework.org/schema/integration"
+	xmlns:int-flow="http://www.springframework.org/schema/integration/flow"
+	xmlns:util="http://www.springframework.org/schema/util"
+	xsi:schemaLocation="http://www.springframework.org/schema/integration http://www.springframework.org/schema/integration/spring-integration.xsd
+		http://www.springframework.org/schema/integration/flow http://www.springframework.org/schema/integration/flow/spring-integration-flow-2.0.xsd
+		http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
+		http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.1.xsd">
+
+ <!-- Instantiate the flow -->
+    <int-flow:flow id="no-response"/>
+     <int-flow:flow id="optional-response"/>
+    
+    <int-flow:outbound-gateway 
+        flow="no-response" input-channel="inputC"/>
+    
+     <int-flow:outbound-gateway 
+        flow="optional-response" input-channel="inputCO" output-channel="outputC"/>    
+    
+    <int:channel id="outputC"/>
+    
+</beans>

src/test/resources/META-INF/spring/integration/flows/no-response/flow-context.xml

@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<beans xmlns="http://www.springframework.org/schema/beans"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xmlns:util="http://www.springframework.org/schema/util"
+	xmlns:int="http://www.springframework.org/schema/integration"
+	xmlns:int-flow="http://www.springframework.org/schema/integration/flow"
+	xsi:schemaLocation="http://www.springframework.org/schema/integration http://www.springframework.org/schema/integration/spring-integration-2.0.xsd
+		http://www.springframework.org/schema/integration/flow http://www.springframework.org/schema/integration/flow/spring-integration-flow-2.0.xsd
+		http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
+		http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.0.xsd">
+
+	<int-flow:flow-configuration> 
+		<int-flow:port-mapping>
+			<int-flow:input-port name="input" channel="flow-input"/> 
+		</int-flow:port-mapping>
+	</int-flow:flow-configuration>
+
+	<int:bridge input-channel="flow-input" output-channel="nullChannel"/>
+	 
+	 
+
+</beans>

src/test/resources/META-INF/spring/integration/flows/optional-response/flow-context.xml

@@ -0,0 +1,28 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<beans xmlns="http://www.springframework.org/schema/beans"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xmlns:util="http://www.springframework.org/schema/util"
+	xmlns:int="http://www.springframework.org/schema/integration"
+	xmlns:int-flow="http://www.springframework.org/schema/integration/flow"
+	xsi:schemaLocation="http://www.springframework.org/schema/integration http://www.springframework.org/schema/integration/spring-integration-2.0.xsd
+		http://www.springframework.org/schema/integration/flow http://www.springframework.org/schema/integration/flow/spring-integration-flow-2.0.xsd
+		http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
+		http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.0.xsd">
+
+	<int-flow:flow-configuration> 
+		<int-flow:port-mapping>
+			<int-flow:input-port name="input" channel="flow-input"/> 
+            <int-flow:output-port name="output" channel="flow-output"/> 
+		</int-flow:port-mapping>
+	</int-flow:flow-configuration>
+
+    <int:filter input-channel="flow-input" 
+        output-channel="flow-output"
+        expression="@random.nextInt(2)==0">
+    </int:filter>
+  
+    <bean id="random" class="java.util.Random"/>
+	 
+	<int:channel id="flow-output"/> 
+
+</beans>