Support for populating model attributes through data class constructors

Includes a new overloaded ModelAndView constructor with an HttpStatus argument, as well as a HandlerMethodArgumentResolverSupport refactoring (revised checkParameterType signature, actually implementing the HandlerMethodArgumentResolver interface).

Issue: SPR-15199

spring-webmvc/src/test/java/org/springframework/web/servlet/mvc/method/annotation/ServletAnnotationControllerHandlerMethodTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -16,6 +16,7 @@
 
 package org.springframework.web.servlet.mvc.method.annotation;
 
+import java.beans.ConstructorProperties;
 import java.beans.PropertyEditorSupport;
 import java.io.IOException;
 import java.io.Serializable;
@@ -140,14 +141,7 @@ import org.springframework.web.servlet.mvc.support.RedirectAttributes;
 import org.springframework.web.servlet.support.RequestContextUtils;
 import org.springframework.web.servlet.view.InternalResourceViewResolver;
 
-import static org.junit.Assert.assertArrayEquals;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertNull;
-import static org.junit.Assert.assertSame;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
+import static org.junit.Assert.*;
 
 /**
  * @author Rossen Stoyanchev
@@ -283,15 +277,13 @@ public class ServletAnnotationControllerHandlerMethodTests extends AbstractServl
 		}, NestedSetController.class);
 
 		MockHttpServletRequest request = new MockHttpServletRequest("GET", "/myPath.do");
-		request.addParameter("testBeanSet", new String[] {"1", "2"});
+		request.addParameter("testBeanSet", "1", "2");
 		MockHttpServletResponse response = new MockHttpServletResponse();
 		getServlet().service(request, response);
 		assertEquals("[1, 2]-org.springframework.tests.sample.beans.TestBean", response.getContentAsString());
 	}
 
-	// SPR-12903
-
-	@Test
+	@Test  // SPR-12903
 	public void pathVariableWithCustomConverter() throws Exception {
 		initServlet(new ApplicationContextInitializer<GenericWebApplicationContext>() {
 			@Override
@@ -1244,9 +1236,7 @@ public class ServletAnnotationControllerHandlerMethodTests extends AbstractServl
 		assertEquals("myParam-42", response.getContentAsString());
 	}
 
-	// SPR-9062
-
-	@Test
+	@Test  // SPR-9062
 	public void ambiguousPathAndRequestMethod() throws Exception {
 		initServletWithControllers(AmbiguousPathAndRequestMethodController.class);
 
@@ -1498,9 +1488,7 @@ public class ServletAnnotationControllerHandlerMethodTests extends AbstractServl
 		assertEquals(405, response.getStatus());
 	}
 
-	// SPR-8536
-
-	@Test
+	@Test  // SPR-8536
 	public void testHeadersCondition() throws Exception {
 		initServletWithControllers(HeadersConditionController.class);
 
@@ -1571,7 +1559,7 @@ public class ServletAnnotationControllerHandlerMethodTests extends AbstractServl
 		assertTrue(RequestContextUtils.getOutputFlashMap(request).isEmpty());
 	}
 
-	@Test // SPR-15176
+	@Test  // SPR-15176
 	public void flashAttributesWithResponseEntity() throws Exception {
 		initServletWithControllers(RedirectAttributesController.class);
 
@@ -1831,6 +1819,31 @@ public class ServletAnnotationControllerHandlerMethodTests extends AbstractServl
 		assertTrue(response.getContentAsByteArray().length == 0);
 	}
 
+	@Test
+	public void dataClassBinding() throws ServletException, IOException {
+		initServletWithControllers(DataClassController.class);
+
+		MockHttpServletRequest request = new MockHttpServletRequest("GET", "/bind");
+		request.addParameter("param1", "value1");
+		request.addParameter("param2", "2");
+		MockHttpServletResponse response = new MockHttpServletResponse();
+		getServlet().service(request, response);
+		assertEquals("value1-2-0", response.getContentAsString());
+	}
+
+	@Test
+	public void dataClassBindingWithAdditionalSetter() throws ServletException, IOException {
+		initServletWithControllers(DataClassController.class);
+
+		MockHttpServletRequest request = new MockHttpServletRequest("GET", "/bind");
+		request.addParameter("param1", "value1");
+		request.addParameter("param2", "2");
+		request.addParameter("param3", "3");
+		MockHttpServletResponse response = new MockHttpServletResponse();
+		getServlet().service(request, response);
+		assertEquals("value1-2-3", response.getContentAsString());
+	}
+
 
 	@Controller
 	static class ControllerWithEmptyValueMapping {
@@ -2727,15 +2740,12 @@ public class ServletAnnotationControllerHandlerMethodTests extends AbstractServl
 
 	@XmlRootElement
 	public static class A {
-
 	}
 
 	@XmlRootElement
 	public static class B {
-
 	}
 
-
 	public static class NotReadableMessageConverter implements HttpMessageConverter<Object> {
 
 		@Override
@@ -3313,7 +3323,6 @@ public class ServletAnnotationControllerHandlerMethodTests extends AbstractServl
 		public HttpHeaders createNoHeader() throws URISyntaxException {
 			return new HttpHeaders();
 		}
-
 	}
 
 	@RestController
@@ -3345,7 +3354,7 @@ public class ServletAnnotationControllerHandlerMethodTests extends AbstractServl
 
 		@RequestMapping("/path")
 		public ModelAndView methodWithHttpStatus(MyEntity object) {
-			return new ModelAndView("view", new ModelMap(), HttpStatus.UNPROCESSABLE_ENTITY);
+			return new ModelAndView("view", HttpStatus.UNPROCESSABLE_ENTITY);
 		}
 
 		@RequestMapping("/exception")
@@ -3355,7 +3364,7 @@ public class ServletAnnotationControllerHandlerMethodTests extends AbstractServl
 
 		@ExceptionHandler(TestException.class)
 		public ModelAndView handleException() {
-			return new ModelAndView("view", new ModelMap(), HttpStatus.UNPROCESSABLE_ENTITY);
+			return new ModelAndView("view", HttpStatus.UNPROCESSABLE_ENTITY);
 		}
 
 		@SuppressWarnings("serial")
@@ -3363,4 +3372,32 @@ public class ServletAnnotationControllerHandlerMethodTests extends AbstractServl
 		}
 	}
 
+	public static class DataClass {
+
+		public final String param1;
+
+		public final int param2;
+
+		public int param3;
+
+		@ConstructorProperties({"param1", "param2"})
+		public DataClass(String param1, int p2) {
+			this.param1 = param1;
+			this.param2 = p2;
+		}
+
+		public void setParam3(int param3) {
+			this.param3 = param3;
+		}
+	}
+
+	@RestController
+	public static class DataClassController {
+
+		@RequestMapping("/bind")
+		public String handle(DataClass data) {
+			return data.param1 + "-" + data.param2 + "-" + data.param3;
+		}
+	}
+
 }