INT-1205 no longer throwing an exception when the $ prefix exists on a header being mapped from a gateway invocation

spring-integration-core/src/main/java/org/springframework/integration/handler/ArgumentArrayMessageMapper.java

@@ -30,7 +30,6 @@ import org.springframework.integration.annotation.Header;
 import org.springframework.integration.annotation.Headers;
 import org.springframework.integration.annotation.Payload;
 import org.springframework.integration.core.Message;
-import org.springframework.integration.core.MessageHeaders;
 import org.springframework.integration.core.MessagingException;
 import org.springframework.integration.message.InboundMessageMapper;
 import org.springframework.integration.message.MessageBuilder;
@@ -148,10 +147,6 @@ public class ArgumentArrayMessageMapper implements InboundMessageMapper<Object[]
 				else if (annotation.annotationType().equals(Header.class)) {
 					Header headerAnnotation = (Header) annotation;
 					String headerName = this.determineHeaderName(headerAnnotation, methodParameter);
-					if (headerName.startsWith(MessageHeaders.PREFIX)){
-						throw new IllegalArgumentException("Attempting to set header: " + headerName + ". Prefix: '" 
-								+ MessageHeaders.PREFIX + "' is reservered for SI internal use");
-					}
 					if (headerAnnotation.required() && argumentValue == null) {
 						throw new IllegalArgumentException("Received null argument value for required header: '" + headerName + "'");
 					}

spring-integration-core/src/test/java/org/springframework/integration/gateway/GatewayWithHeaderAnnotations-context.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<beans:beans xmlns="http://www.springframework.org/schema/integration"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xmlns:beans="http://www.springframework.org/schema/beans"
+	xsi:schemaLocation="http://www.springframework.org/schema/beans
+			http://www.springframework.org/schema/beans/spring-beans.xsd
+			http://www.springframework.org/schema/integration
+			http://www.springframework.org/schema/integration/spring-integration.xsd">
+
+	<gateway id="gateway"
+			 default-request-channel="requestChannel"
+			 service-interface="org.springframework.integration.gateway.GatewayWithHeaderAnnotations$TestService" />
+
+	<service-activator input-channel="requestChannel" expression="payload + headers.$priority"/>
+
+</beans:beans>

spring-integration-core/src/test/java/org/springframework/integration/gateway/GatewayWithHeaderAnnotations.java

@@ -0,0 +1,56 @@
+/*
+ * Copyright 2002-2010 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.integration.gateway;
+
+import static org.junit.Assert.assertEquals;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.ApplicationContext;
+import org.springframework.integration.annotation.Header;
+import org.springframework.integration.core.MessageHeaders;
+import org.springframework.integration.core.MessagePriority;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+/**
+ * @author Mark Fisher
+ * @since 2.0
+ */
+@ContextConfiguration
+@RunWith(SpringJUnit4ClassRunner.class)
+public class GatewayWithHeaderAnnotations {
+
+	@Autowired
+	private ApplicationContext applicationContext;
+
+
+	@Test // INT-1205
+	public void priorityAsArgument() {
+		TestService gateway = (TestService) applicationContext.getBean("gateway");
+		String result = gateway.test("foo", MessagePriority.HIGH);
+		assertEquals("fooHIGH", result);
+	}
+
+
+	public static interface TestService {
+		public String test(String str, @Header(MessageHeaders.PRIORITY) MessagePriority priority);
+	}
+
+}