SPR-8976 Make flash attrs available to view controllers.

Previously flash attributes were automatically merged into the
model of annotated controllers only. This change extends the same
benefit to ParameterizableView- and UrlFilenameViewController,
both of which merely select a view without user controller logic
and (the views) would otherwise  not have access to the flash
attributes.

Author: rstoyanchev

org.springframework.web.servlet/src/main/java/org/springframework/web/servlet/mvc/AbstractUrlViewController.java

@@ -21,6 +21,7 @@
 
 import org.springframework.util.Assert;
 import org.springframework.web.servlet.ModelAndView;
+import org.springframework.web.servlet.support.RequestContextUtils;
 import org.springframework.web.util.UrlPathHelper;
 
 /**
@@ -86,7 +87,8 @@ protected UrlPathHelper getUrlPathHelper() {
 
 	/**
 	 * Retrieves the URL path to use for lookup and delegates to
-	 * {@link #getViewNameForRequest}.
+	 * {@link #getViewNameForRequest}. Also adds the content of 
+	 * {@link RequestContextUtils#getInputFlashMap} to the model.
 	 */
 	@Override
 	protected ModelAndView handleRequestInternal(HttpServletRequest request, HttpServletResponse response) {
@@ -95,7 +97,7 @@ protected ModelAndView handleRequestInternal(HttpServletRequest request, HttpSer
 		if (logger.isDebugEnabled()) {
 			logger.debug("Returning view name '" + viewName + "' for lookup path [" + lookupPath + "]");
 		}
-		return new ModelAndView(viewName);
+		return new ModelAndView(viewName, RequestContextUtils.getInputFlashMap(request));
 	}
 
 	/**

org.springframework.web.servlet/src/main/java/org/springframework/web/servlet/mvc/ParameterizableViewController.java

@@ -20,6 +20,7 @@
 import javax.servlet.http.HttpServletResponse;
 
 import org.springframework.web.servlet.ModelAndView;
+import org.springframework.web.servlet.support.RequestContextUtils;
 
 /**
  * <p>Trivial controller that always returns a named view. The view
@@ -87,12 +88,13 @@ public String getViewName() {
 
 	/**
 	 * Return a ModelAndView object with the specified view name.
+	 * The content of {@link RequestContextUtils#getInputFlashMap} is also added to the model.
 	 * @see #getViewName()
 	 */
 	@Override
 	protected ModelAndView handleRequestInternal(HttpServletRequest request, HttpServletResponse response)
 			throws Exception {
-		return new ModelAndView(getViewName());
+		return new ModelAndView(getViewName(), RequestContextUtils.getInputFlashMap(request));
 	}
 
 }

org.springframework.web.servlet/src/test/java/org/springframework/web/servlet/mvc/ParameterizableViewControllerTests.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright 2002-2012 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.web.servlet.mvc;
+
+import static org.junit.Assert.*;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.springframework.mock.web.MockHttpServletRequest;
+import org.springframework.mock.web.MockHttpServletResponse;
+import org.springframework.ui.ModelMap;
+import org.springframework.web.servlet.FlashMapManager;
+import org.springframework.web.servlet.ModelAndView;
+
+/**
+ * Test fixture with a ParameterizableViewController.
+ *
+ * @author Rossen Stoyanchev
+ * @since 3.1.1
+ */
+public class ParameterizableViewControllerTests {
+
+	private ParameterizableViewController controller;
+
+	private MockHttpServletRequest request;
+	
+	@Before
+	public void setup() {
+		this.controller = new ParameterizableViewController();
+		this.request = new MockHttpServletRequest("GET", "/");
+	}
+
+	@Test
+	public void handleRequestWithViewName() throws Exception {
+		String viewName = "testView";
+		this.controller.setViewName(viewName);
+		ModelAndView mav = this.controller.handleRequest(this.request, new MockHttpServletResponse());
+		assertEquals(viewName, mav.getViewName());
+		assertTrue(mav.getModel().isEmpty());
+	}
+	
+	@Test
+	public void handleRequestWithoutViewName() throws Exception {
+		ModelAndView mav = this.controller.handleRequest(this.request, new MockHttpServletResponse());
+		assertNull(mav.getViewName());
+		assertTrue(mav.getModel().isEmpty());
+	}
+
+	@Test
+	public void handleRequestWithFlashAttributes() throws Exception {
+		this.request.setAttribute(FlashMapManager.INPUT_FLASH_MAP_ATTRIBUTE, new ModelMap("name", "value"));
+		ModelAndView mav = this.controller.handleRequest(this.request, new MockHttpServletResponse());
+		assertEquals(1, mav.getModel().size());
+		assertEquals("value", mav.getModel().get("name"));
+	}
+
+}

org.springframework.web.servlet/src/test/java/org/springframework/web/servlet/mvc/UrlFilenameViewControllerTests.java

@@ -20,8 +20,10 @@
 
 import org.springframework.mock.web.MockHttpServletRequest;
 import org.springframework.mock.web.MockHttpServletResponse;
+import org.springframework.ui.ModelMap;
 import org.springframework.util.AntPathMatcher;
 import org.springframework.util.PathMatcher;
+import org.springframework.web.servlet.FlashMapManager;
 import org.springframework.web.servlet.HandlerMapping;
 import org.springframework.web.servlet.ModelAndView;
 
@@ -150,6 +152,17 @@ public void testNestedPathisUsedAsViewName_InBreakingChangeFromSpring12Line() th
 		assertTrue(mv.getModel().isEmpty());
 	}
 
+	public void testWithFlashAttributes() throws Exception {
+		UrlFilenameViewController ctrl = new UrlFilenameViewController();
+		MockHttpServletRequest request = new MockHttpServletRequest("GET", "/index");
+		request.setAttribute(FlashMapManager.INPUT_FLASH_MAP_ATTRIBUTE, new ModelMap("name", "value"));
+		MockHttpServletResponse response = new MockHttpServletResponse();
+		ModelAndView mv = ctrl.handleRequest(request, response);
+		assertEquals("index", mv.getViewName());
+		assertEquals(1, mv.getModel().size());
+		assertEquals("value", mv.getModel().get("name"));
+	}
+
 	private void exposePathInMapping(MockHttpServletRequest request, String mapping) {
 		String pathInMapping = this.pathMatcher.extractPathWithinPattern(mapping, request.getRequestURI());
 		request.setAttribute(HandlerMapping.PATH_WITHIN_HANDLER_MAPPING_ATTRIBUTE, pathInMapping);