Add a ResolvableType field to HandlerResult

This change allows to be able to check generic type on the return value
at HandlerAdapter and ResultHandler level. For example, it allows to do
a Publisher<Void> check in SimpleHandlerResultHandler.

spring-web-reactive/src/test/java/org/springframework/reactive/web/dispatch/SimpleHandlerResultHandlerTests.java

@@ -0,0 +1,68 @@
+/*
+ * Copyright 2002-2015 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.reactive.web.dispatch;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import org.junit.Test;
+import org.reactivestreams.Publisher;
+
+import org.springframework.core.ResolvableType;
+import org.springframework.web.method.HandlerMethod;
+
+/**
+ * @author Sebastien Deleuze
+ */
+public class SimpleHandlerResultHandlerTests {
+
+	@Test
+	public void supports() throws NoSuchMethodException {
+
+		SimpleHandlerResultHandler resultHandler = new SimpleHandlerResultHandler();
+		TestController controller = new TestController();
+
+		HandlerMethod hm = new HandlerMethod(controller, TestController.class.getMethod("voidReturnValue"));
+		ResolvableType type = ResolvableType.forMethodParameter(hm.getReturnType());
+		assertFalse(resultHandler.supports(new HandlerResult(hm, null, type)));
+
+		hm = new HandlerMethod(controller, TestController.class.getMethod("publisherString"));
+		type = ResolvableType.forMethodParameter(hm.getReturnType());
+		assertFalse(resultHandler.supports(new HandlerResult(hm, null, type)));
+
+		hm = new HandlerMethod(controller, TestController.class.getMethod("publisherVoid"));
+		type = ResolvableType.forMethodParameter(hm.getReturnType());
+		assertTrue(resultHandler.supports(new HandlerResult(hm, null, type)));
+	}
+
+
+	@SuppressWarnings("unused")
+	private static class TestController {
+
+		public Publisher<String> voidReturnValue() {
+			return null;
+		}
+
+		public Publisher<String> publisherString() {
+			return null;
+		}
+
+		public Publisher<Void> publisherVoid() {
+			return null;
+		}
+	}
+
+}

spring-web-reactive/src/test/java/org/springframework/reactive/web/dispatch/method/annotation/ResponseBodyResultHandlerTests.java

@@ -21,6 +21,7 @@ import java.util.Collections;
 import org.junit.Test;
 import org.reactivestreams.Publisher;
 
+import org.springframework.core.ResolvableType;
 import org.springframework.core.convert.support.DefaultConversionService;
 import org.springframework.reactive.codec.encoder.StringEncoder;
 import org.springframework.reactive.web.dispatch.HandlerResult;
@@ -43,13 +44,16 @@ public class ResponseBodyResultHandlerTests {
 		TestController controller = new TestController();
 
 		HandlerMethod hm = new HandlerMethod(controller,TestController.class.getMethod("notAnnotated"));
-		assertFalse(handler.supports(new HandlerResult(hm, null)));
+		ResolvableType type = ResolvableType.forMethodParameter(hm.getReturnType());
+		assertFalse(handler.supports(new HandlerResult(hm, null, type)));
 
 		hm = new HandlerMethod(controller, TestController.class.getMethod("publisherString"));
-		assertTrue(handler.supports(new HandlerResult(hm, null)));
+		type = ResolvableType.forMethodParameter(hm.getReturnType());
+		assertTrue(handler.supports(new HandlerResult(hm, null, type)));
 
 		hm = new HandlerMethod(controller, TestController.class.getMethod("publisherVoid"));
-		assertTrue(handler.supports(new HandlerResult(hm, null)));
+		type = ResolvableType.forMethodParameter(hm.getReturnType());
+		assertTrue(handler.supports(new HandlerResult(hm, null, type)));
 	}