Added validation and tests (exactly 1 Message or payload when mapping with toMessage(), etc).

org.springframework.integration/src/test/java/org/springframework/integration/message/MethodParameterMessageMapperInitializationTests.java

@@ -0,0 +1,57 @@
+/*
+ * Copyright 2002-2008 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.message;
+
+import java.lang.reflect.Method;
+
+import org.junit.Test;
+
+/**
+ * @author Mark Fisher
+ */
+public class MethodParameterMessageMapperInitializationTests {
+
+	@Test(expected = IllegalArgumentException.class)
+	public void messageAndPayload() throws Exception {
+		Method method = TestService.class.getMethod("messageAndPayload", Message.class, String.class);
+		new MethodParameterMessageMapper(method);
+	}
+
+	@Test(expected = IllegalArgumentException.class)
+	public void twoMessages() throws Exception {
+		Method method = TestService.class.getMethod("twoMessages", Message.class, Message.class);
+		new MethodParameterMessageMapper(method);
+	}
+
+	@Test(expected = IllegalArgumentException.class)
+	public void twoPayloads() throws Exception {
+		Method method = TestService.class.getMethod("twoPayloads", String.class, String.class);
+		new MethodParameterMessageMapper(method);
+	}
+
+
+	private static interface TestService {
+
+		void messageAndPayload(Message<?> message, String foo);
+
+		void twoMessages(Message<?> message1, Message<?> message2);
+
+		void twoPayloads(String foo, String bar);
+
+	}
+
+}

org.springframework.integration/src/test/java/org/springframework/integration/message/MethodParameterMessageMapperToMessageTests.java

@@ -173,6 +173,20 @@ public class MethodParameterMessageMapperToMessageTests {
 		assertNull(message.getHeaders().get("foo"));
 	}
 
+	@Test(expected = IllegalArgumentException.class)
+	public void noArgs() throws Exception {
+		Method method = TestService.class.getMethod("noArgs", new Class<?>[] {});
+		MethodParameterMessageMapper mapper = new MethodParameterMessageMapper(method);
+		mapper.toMessage(new Object[] {});
+	}
+
+	@Test(expected = IllegalArgumentException.class)
+	public void onlyHeaders() throws Exception {
+		Method method = TestService.class.getMethod("onlyHeaders", String.class, String.class);
+		MethodParameterMessageMapper mapper = new MethodParameterMessageMapper(method);
+		mapper.toMessage(new Object[] { "abc", "def" });
+	}
+
 
 	private static interface TestService {
 
@@ -190,6 +204,12 @@ public class MethodParameterMessageMapperToMessageTests {
 
 		void sendMessageAndOptionalHeader(Message<?> message, @Header(value="foo", required=false) String foo);
 
+		// invalid methods
+
+		void noArgs();
+
+		void onlyHeaders(@Header("foo") String foo, @Header("bar") String bar);
+
 	}
 
 }