Consistent support for path variable and multipart binding

Closes gh-24107
Closes gh-22169
Closes gh-25265

spring-web/src/main/java/org/springframework/web/bind/ServletRequestDataBinder.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -17,11 +17,14 @@
 package org.springframework.web.bind;
 
 import javax.servlet.ServletRequest;
+import javax.servlet.http.HttpServletRequest;
 
 import org.springframework.beans.MutablePropertyValues;
 import org.springframework.lang.Nullable;
+import org.springframework.util.StringUtils;
 import org.springframework.validation.BindException;
 import org.springframework.web.multipart.MultipartRequest;
+import org.springframework.web.multipart.support.StandardServletPartUtils;
 import org.springframework.web.util.WebUtils;
 
 /**
@@ -103,6 +106,12 @@ public class ServletRequestDataBinder extends WebDataBinder {
 		if (multipartRequest != null) {
 			bindMultipart(multipartRequest.getMultiFileMap(), mpvs);
 		}
+		else if (StringUtils.startsWithIgnoreCase(request.getContentType(), "multipart/")) {
+			HttpServletRequest httpServletRequest = WebUtils.getNativeRequest(request, HttpServletRequest.class);
+			if (httpServletRequest != null) {
+				StandardServletPartUtils.bindParts(httpServletRequest, mpvs, isBindEmptyMultipartFiles());
+			}
+		}
 		addBindValues(mpvs, request);
 		doBind(mpvs);
 	}

spring-web/src/main/java/org/springframework/web/bind/support/WebExchangeDataBinder.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -37,6 +37,7 @@ import org.springframework.web.server.ServerWebExchange;
  * binding from URL query params or form data in the request data to Java objects.
  *
  * @author Rossen Stoyanchev
+ * @author Juergen Hoeller
  * @since 5.0
  */
 public class WebExchangeDataBinder extends WebDataBinder {
@@ -64,7 +65,7 @@ public class WebExchangeDataBinder extends WebDataBinder {
 
 	/**
 	 * Bind query params, form data, and or multipart form data to the binder target.
-	 * @param exchange the current exchange.
+	 * @param exchange the current exchange
 	 * @return a {@code Mono<Void>} when binding is complete
 	 */
 	public Mono<Void> bind(ServerWebExchange exchange) {
@@ -76,8 +77,11 @@ public class WebExchangeDataBinder extends WebDataBinder {
 	/**
 	 * Protected method to obtain the values for data binding. By default this
 	 * method delegates to {@link #extractValuesToBind(ServerWebExchange)}.
+	 * @param exchange the current exchange
+	 * @return a map of bind values
+	 * @since 5.3
 	 */
-	protected Mono<Map<String, Object>> getValuesToBind(ServerWebExchange exchange) {
+	public Mono<Map<String, Object>> getValuesToBind(ServerWebExchange exchange) {
 		return extractValuesToBind(exchange);
 	}
 
@@ -107,7 +111,7 @@ public class WebExchangeDataBinder extends WebDataBinder {
 				});
 	}
 
-	private static void addBindValue(Map<String, Object> params, String key, List<?> values) {
+	protected static void addBindValue(Map<String, Object> params, String key, List<?> values) {
 		if (!CollectionUtils.isEmpty(values)) {
 			values = values.stream()
 					.map(value -> value instanceof FormFieldPart ? ((FormFieldPart) value).value() : value)

spring-web/src/main/java/org/springframework/web/bind/support/WebRequestDataBinder.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -17,19 +17,16 @@
 package org.springframework.web.bind.support;
 
 import javax.servlet.http.HttpServletRequest;
-import javax.servlet.http.Part;
 
 import org.springframework.beans.MutablePropertyValues;
 import org.springframework.lang.Nullable;
-import org.springframework.util.LinkedMultiValueMap;
-import org.springframework.util.MultiValueMap;
 import org.springframework.util.StringUtils;
 import org.springframework.validation.BindException;
 import org.springframework.web.bind.WebDataBinder;
 import org.springframework.web.context.request.NativeWebRequest;
 import org.springframework.web.context.request.WebRequest;
-import org.springframework.web.multipart.MultipartException;
 import org.springframework.web.multipart.MultipartRequest;
+import org.springframework.web.multipart.support.StandardServletPartUtils;
 
 /**
  * Special {@link org.springframework.validation.DataBinder} to perform data binding
@@ -109,53 +106,21 @@ public class WebRequestDataBinder extends WebDataBinder {
 	 */
 	public void bind(WebRequest request) {
 		MutablePropertyValues mpvs = new MutablePropertyValues(request.getParameterMap());
-		if (isMultipartRequest(request) && request instanceof NativeWebRequest) {
+		if (request instanceof NativeWebRequest) {
 			MultipartRequest multipartRequest = ((NativeWebRequest) request).getNativeRequest(MultipartRequest.class);
 			if (multipartRequest != null) {
 				bindMultipart(multipartRequest.getMultiFileMap(), mpvs);
 			}
-			else {
+			else if (StringUtils.startsWithIgnoreCase(request.getHeader("Content-Type"), "multipart/")) {
 				HttpServletRequest servletRequest = ((NativeWebRequest) request).getNativeRequest(HttpServletRequest.class);
 				if (servletRequest != null) {
-					bindParts(servletRequest, mpvs);
+					StandardServletPartUtils.bindParts(servletRequest, mpvs, isBindEmptyMultipartFiles());
 				}
 			}
 		}
 		doBind(mpvs);
 	}
 
-	/**
-	 * Check if the request is a multipart request (by checking its Content-Type header).
-	 * @param request the request with parameters to bind
-	 */
-	private boolean isMultipartRequest(WebRequest request) {
-		String contentType = request.getHeader("Content-Type");
-		return StringUtils.startsWithIgnoreCase(contentType, "multipart");
-	}
-
-	private void bindParts(HttpServletRequest request, MutablePropertyValues mpvs) {
-		try {
-			MultiValueMap<String, Part> map = new LinkedMultiValueMap<>();
-			for (Part part : request.getParts()) {
-				map.add(part.getName(), part);
-			}
-			map.forEach((key, values) -> {
-				if (values.size() == 1) {
-					Part part = values.get(0);
-					if (isBindEmptyMultipartFiles() || part.getSize() > 0) {
-						mpvs.add(key, part);
-					}
-				}
-				else {
-					mpvs.add(key, values);
-				}
-			});
-		}
-		catch (Exception ex) {
-			throw new MultipartException("Failed to get request parts", ex);
-		}
-	}
-
 	/**
 	 * Treats errors as fatal.
 	 * <p>Use this method only if it's an error if the input isn't valid.

spring-web/src/main/java/org/springframework/web/method/annotation/ModelAttributeMethodProcessor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -28,6 +28,9 @@ import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
 
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.Part;
+
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
@@ -39,6 +42,7 @@ import org.springframework.core.ParameterNameDiscoverer;
 import org.springframework.core.annotation.AnnotationUtils;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
+import org.springframework.util.StringUtils;
 import org.springframework.validation.BindException;
 import org.springframework.validation.BindingResult;
 import org.springframework.validation.Errors;
@@ -53,6 +57,9 @@ import org.springframework.web.context.request.NativeWebRequest;
 import org.springframework.web.method.support.HandlerMethodArgumentResolver;
 import org.springframework.web.method.support.HandlerMethodReturnValueHandler;
 import org.springframework.web.method.support.ModelAndViewContainer;
+import org.springframework.web.multipart.MultipartFile;
+import org.springframework.web.multipart.MultipartRequest;
+import org.springframework.web.multipart.support.StandardServletPartUtils;
 
 /**
  * Resolve {@code @ModelAttribute} annotated method arguments and handle
@@ -242,15 +249,9 @@ public class ModelAttributeMethodProcessor implements HandlerMethodArgumentResol
 	 * @throws Exception in case of constructor invocation failure
 	 * @since 5.1
 	 */
-	@SuppressWarnings("deprecation")
 	protected Object constructAttribute(Constructor<?> ctor, String attributeName, MethodParameter parameter,
 			WebDataBinderFactory binderFactory, NativeWebRequest webRequest) throws Exception {
 
-		Object constructed = constructAttribute(ctor, attributeName, binderFactory, webRequest);
-		if (constructed != null) {
-			return constructed;
-		}
-
 		if (ctor.getParameterCount() == 0) {
 			// A single default constructor -> clearly a standard JavaBeans arrangement.
 			return BeanUtils.instantiateClass(ctor);
@@ -279,10 +280,13 @@ public class ModelAttributeMethodProcessor implements HandlerMethodArgumentResol
 				if (fieldDefaultPrefix != null) {
 					value = webRequest.getParameter(fieldDefaultPrefix + paramName);
 				}
-				if (value == null && fieldMarkerPrefix != null) {
+				if (value == null) {
-					if (webRequest.getParameter(fieldMarkerPrefix + paramName) != null) {
+					if (fieldMarkerPrefix != null && webRequest.getParameter(fieldMarkerPrefix + paramName) != null) {
 						value = binder.getEmptyValue(paramType);
 					}
+					else {
+						value = resolveConstructorArgument(paramName, paramType, webRequest);
+					}
 				}
 			}
 			try {
@@ -320,20 +324,6 @@ public class ModelAttributeMethodProcessor implements HandlerMethodArgumentResol
 		return BeanUtils.instantiateClass(ctor, args);
 	}
 
-	/**
-	 * Construct a new attribute instance with the given constructor.
-	 * @since 5.0
-	 * @deprecated as of 5.1, in favor of
-	 * {@link #constructAttribute(Constructor, String, MethodParameter, WebDataBinderFactory, NativeWebRequest)}
-	 */
-	@Deprecated
-	@Nullable
-	protected Object constructAttribute(Constructor<?> ctor, String attributeName,
-			WebDataBinderFactory binderFactory, NativeWebRequest webRequest) throws Exception {
-
-		return null;
-	}
-
 	/**
 	 * Extension point to bind the request to the target object.
 	 * @param binder the data binder instance to use for the binding
@@ -343,6 +333,29 @@ public class ModelAttributeMethodProcessor implements HandlerMethodArgumentResol
 		((WebRequestDataBinder) binder).bind(request);
 	}
 
+	@Nullable
+	public Object resolveConstructorArgument(String paramName, Class<?> paramType, NativeWebRequest request)
+			throws Exception {
+
+		MultipartRequest multipartRequest = request.getNativeRequest(MultipartRequest.class);
+		if (multipartRequest != null) {
+			List<MultipartFile> files = multipartRequest.getFiles(paramName);
+			if (!files.isEmpty()) {
+				return (files.size() == 1 ? files.get(0) : files);
+			}
+		}
+		else if (StringUtils.startsWithIgnoreCase(request.getHeader("Content-Type"), "multipart/")) {
+			HttpServletRequest servletRequest = request.getNativeRequest(HttpServletRequest.class);
+			if (servletRequest != null) {
+				List<Part> parts = StandardServletPartUtils.getParts(servletRequest, paramName);
+				if (!parts.isEmpty()) {
+					return (parts.size() == 1 ? parts.get(0) : parts);
+				}
+			}
+		}
+		return null;
+	}
+
 	/**
 	 * Validate the model attribute if applicable.
 	 * <p>The default implementation checks for {@code @javax.validation.Valid},

spring-web/src/main/java/org/springframework/web/multipart/support/StandardServletPartUtils.java

@@ -0,0 +1,104 @@
+/*
+ * Copyright 2002-2020 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
+ *
+ *      https://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.multipart.support;
+
+import java.util.LinkedList;
+import java.util.List;
+
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.Part;
+
+import org.springframework.beans.MutablePropertyValues;
+import org.springframework.util.LinkedMultiValueMap;
+import org.springframework.util.MultiValueMap;
+import org.springframework.web.multipart.MultipartException;
+
+/**
+ * Utility methods for standard Servlet {@link Part} handling.
+ *
+ * @author Juergen Hoeller
+ * @since 5.3
+ * @see HttpServletRequest#getParts()
+ * @see StandardServletMultipartResolver
+ */
+public abstract class StandardServletPartUtils {
+
+	/**
+	 * Retrieve all parts from the given servlet request.
+	 * @param request the servlet request
+	 * @return the parts in a MultiValueMap
+	 * @throws MultipartException in case of failures
+	 */
+	public static MultiValueMap<String, Part> getParts(HttpServletRequest request) throws MultipartException {
+		try {
+			MultiValueMap<String, Part> parts = new LinkedMultiValueMap<>();
+			for (Part part : request.getParts()) {
+				parts.add(part.getName(), part);
+			}
+			return parts;
+		}
+		catch (Exception ex) {
+			throw new MultipartException("Failed to get request parts", ex);
+		}
+	}
+
+	/**
+	 * Retrieve all parts with the given name from the given servlet request.
+	 * @param request the servlet request
+	 * @param name the name to look for
+	 * @return the parts in a MultiValueMap
+	 * @throws MultipartException in case of failures
+	 */
+	public static List<Part> getParts(HttpServletRequest request, String name) throws MultipartException {
+		try {
+			List<Part> parts = new LinkedList<>();
+			for (Part part : request.getParts()) {
+				if (part.getName().equals(name)) {
+					parts.add(part);
+				}
+			}
+			return parts;
+		}
+		catch (Exception ex) {
+			throw new MultipartException("Failed to get request parts", ex);
+		}
+	}
+
+	/**
+	 * Bind all parts from the given servlet request.
+	 * @param request the servlet request
+	 * @param mpvs the property values to bind to
+	 * @param bindEmpty whether to bind empty parts as well
+	 * @throws MultipartException in case of failures
+	 */
+	public static void bindParts(HttpServletRequest request, MutablePropertyValues mpvs, boolean bindEmpty)
+			throws MultipartException {
+
+		getParts(request).forEach((key, values) -> {
+			if (values.size() == 1) {
+				Part part = values.get(0);
+				if (bindEmpty || part.getSize() > 0) {
+					mpvs.add(key, part);
+				}
+			}
+			else {
+				mpvs.add(key, values);
+			}
+		});
+	}
+
+}

spring-webflux/src/main/java/org/springframework/web/reactive/BindingContext.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -16,8 +16,16 @@
 
 package org.springframework.web.reactive;
 
+import java.util.Collections;
+import java.util.Map;
+import java.util.TreeMap;
+
+import reactor.core.publisher.Mono;
+
+import org.springframework.http.codec.multipart.Part;
 import org.springframework.lang.Nullable;
 import org.springframework.ui.Model;
+import org.springframework.util.MultiValueMap;
 import org.springframework.validation.support.BindingAwareConcurrentModel;
 import org.springframework.web.bind.support.WebBindingInitializer;
 import org.springframework.web.bind.support.WebExchangeDataBinder;
@@ -35,6 +43,7 @@ import org.springframework.web.server.ServerWebExchange;
  * <p>Container for the default model for the request.
  *
  * @author Rossen Stoyanchev
+ * @author Juergen Hoeller
  * @since 5.0
  */
 public class BindingContext {
@@ -79,7 +88,7 @@ public class BindingContext {
 	 * @throws ServerErrorException if {@code @InitBinder} method invocation fails
 	 */
 	public WebExchangeDataBinder createDataBinder(ServerWebExchange exchange, @Nullable Object target, String name) {
-		WebExchangeDataBinder dataBinder = new WebExchangeDataBinder(target, name);
+		WebExchangeDataBinder dataBinder = new ExtendedWebExchangeDataBinder(target, name);
 		if (this.initializer != null) {
 			this.initializer.initBinder(dataBinder);
 		}
@@ -106,4 +115,34 @@ public class BindingContext {
 		return createDataBinder(exchange, null, name);
 	}
 
+
+	/**
+	 * Extended variant of {@link WebExchangeDataBinder}, adding path variables.
+	 */
+	private static class ExtendedWebExchangeDataBinder extends WebExchangeDataBinder {
+
+		public ExtendedWebExchangeDataBinder(@Nullable Object target, String objectName) {
+			super(target, objectName);
+		}
+
+		@Override
+		public Mono<Map<String, Object>> getValuesToBind(ServerWebExchange exchange) {
+			Map<String, String> vars = exchange.getAttributeOrDefault(
+					HandlerMapping.URI_TEMPLATE_VARIABLES_ATTRIBUTE, Collections.emptyMap());
+			MultiValueMap<String, String> queryParams = exchange.getRequest().getQueryParams();
+			Mono<MultiValueMap<String, String>> formData = exchange.getFormData();
+			Mono<MultiValueMap<String, Part>> multipartData = exchange.getMultipartData();
+
+			return Mono.zip(Mono.just(vars), Mono.just(queryParams), formData, multipartData)
+					.map(tuple -> {
+						Map<String, Object> result = new TreeMap<>();
+						tuple.getT1().forEach(result::put);
+						tuple.getT2().forEach((key, values) -> addBindValue(result, key, values));
+						tuple.getT3().forEach((key, values) -> addBindValue(result, key, values));
+						tuple.getT4().forEach((key, values) -> addBindValue(result, key, values));
+						return result;
+					});
+		}
+	}
+
 }

spring-webflux/src/main/java/org/springframework/web/reactive/result/method/annotation/ModelAttributeMethodArgumentResolver.java

@@ -41,7 +41,6 @@ import org.springframework.util.ClassUtils;
 import org.springframework.validation.BindingResult;
 import org.springframework.validation.Errors;
 import org.springframework.validation.annotation.Validated;
-import org.springframework.web.bind.WebDataBinder;
 import org.springframework.web.bind.annotation.ModelAttribute;
 import org.springframework.web.bind.support.WebExchangeBindException;
 import org.springframework.web.bind.support.WebExchangeDataBinder;
@@ -233,7 +232,8 @@ public class ModelAttributeMethodArgumentResolver extends HandlerMethodArgumentR
 		}
 
 		// A single data class constructor -> resolve constructor arguments from request parameters.
-		return WebExchangeDataBinder.extractValuesToBind(exchange).map(bindValues -> {
+		WebExchangeDataBinder binder = context.createDataBinder(exchange, null, attributeName);
+		return getValuesToBind(binder, exchange).map(bindValues -> {
 			ConstructorProperties cp = ctor.getAnnotation(ConstructorProperties.class);
 			String[] paramNames = (cp != null ? cp.value() : parameterNameDiscoverer.getParameterNames(ctor));
 			Assert.state(paramNames != null, () -> "Cannot resolve parameter names for constructor " + ctor);
@@ -241,7 +241,6 @@ public class ModelAttributeMethodArgumentResolver extends HandlerMethodArgumentR
 			Assert.state(paramNames.length == paramTypes.length,
 					() -> "Invalid number of parameter names: " + paramNames.length + " for constructor " + ctor);
 			Object[] args = new Object[paramTypes.length];
-			WebDataBinder binder = context.createDataBinder(exchange, null, attributeName);
 			String fieldDefaultPrefix = binder.getFieldDefaultPrefix();
 			String fieldMarkerPrefix = binder.getFieldMarkerPrefix();
 			for (int i = 0; i < paramNames.length; i++) {
@@ -271,6 +270,18 @@ public class ModelAttributeMethodArgumentResolver extends HandlerMethodArgumentR
 		});
 	}
 
+	/**
+	 * Protected method to obtain the values for data binding. By default this
+	 * method delegates to {@link WebExchangeDataBinder#getValuesToBind}.
+	 * @param binder the data binder in use
+	 * @param exchange the current exchange
+	 * @return a map of bind values
+	 * @since 5.3
+	 */
+	public Mono<Map<String, Object>> getValuesToBind(WebExchangeDataBinder binder, ServerWebExchange exchange) {
+		return binder.getValuesToBind(exchange);
+	}
+
 	private boolean hasErrorsArgument(MethodParameter parameter) {
 		int i = parameter.getParameterIndex();
 		Class<?>[] paramTypes = parameter.getExecutable().getParameterTypes();

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/ExceptionHandlerExceptionResolver.java

@@ -48,7 +48,6 @@ import org.springframework.web.method.ControllerAdviceBean;
 import org.springframework.web.method.HandlerMethod;
 import org.springframework.web.method.annotation.ExceptionHandlerMethodResolver;
 import org.springframework.web.method.annotation.MapMethodProcessor;
-import org.springframework.web.method.annotation.ModelAttributeMethodProcessor;
 import org.springframework.web.method.annotation.ModelMethodProcessor;
 import org.springframework.web.method.support.HandlerMethodArgumentResolver;
 import org.springframework.web.method.support.HandlerMethodArgumentResolverComposite;
@@ -361,7 +360,7 @@ public class ExceptionHandlerExceptionResolver extends AbstractHandlerMethodExce
 				getMessageConverters(), this.contentNegotiationManager, this.responseBodyAdvice));
 
 		// Annotation-based return value types
-		handlers.add(new ModelAttributeMethodProcessor(false));
+		handlers.add(new ServletModelAttributeMethodProcessor(false));
 		handlers.add(new RequestResponseBodyMethodProcessor(
 				getMessageConverters(), this.contentNegotiationManager, this.responseBodyAdvice));
 
@@ -375,7 +374,7 @@ public class ExceptionHandlerExceptionResolver extends AbstractHandlerMethodExce
 		}
 
 		// Catch-all
-		handlers.add(new ModelAttributeMethodProcessor(true));
+		handlers.add(new ServletModelAttributeMethodProcessor(true));
 
 		return handlers;
 	}

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/ExtendedServletRequestDataBinder.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -31,6 +31,8 @@ import org.springframework.web.servlet.HandlerMapping;
  *
  * @author Rossen Stoyanchev
  * @since 3.1
+ * @see ServletRequestDataBinder
+ * @see HandlerMapping#URI_TEMPLATE_VARIABLES_ATTRIBUTE
  */
 public class ExtendedServletRequestDataBinder extends ServletRequestDataBinder {
 
@@ -60,9 +62,9 @@ public class ExtendedServletRequestDataBinder extends ServletRequestDataBinder {
 	 * Merge URI variables into the property values to use for data binding.
 	 */
 	@Override
-	@SuppressWarnings("unchecked")
 	protected void addBindValues(MutablePropertyValues mpvs, ServletRequest request) {
 		String attr = HandlerMapping.URI_TEMPLATE_VARIABLES_ATTRIBUTE;
+		@SuppressWarnings("unchecked")
 		Map<String, String> uriVars = (Map<String, String>) request.getAttribute(attr);
 		if (uriVars != null) {
 			uriVars.forEach((name, value) -> {

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/ModelAndViewResolverMethodReturnValueHandler.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -58,7 +58,8 @@ public class ModelAndViewResolverMethodReturnValueHandler implements HandlerMeth
 	@Nullable
 	private final List<ModelAndViewResolver> mavResolvers;
 
-	private final ModelAttributeMethodProcessor modelAttributeProcessor = new ModelAttributeMethodProcessor(true);
+	private final ModelAttributeMethodProcessor modelAttributeProcessor =
+			new ServletModelAttributeMethodProcessor(true);
 
 
 	/**

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/RequestMappingHandlerAdapter.java

@@ -75,7 +75,6 @@ import org.springframework.web.method.annotation.ErrorsMethodArgumentResolver;
 import org.springframework.web.method.annotation.ExpressionValueMethodArgumentResolver;
 import org.springframework.web.method.annotation.InitBinderDataBinderFactory;
 import org.springframework.web.method.annotation.MapMethodProcessor;
-import org.springframework.web.method.annotation.ModelAttributeMethodProcessor;
 import org.springframework.web.method.annotation.ModelFactory;
 import org.springframework.web.method.annotation.ModelMethodProcessor;
 import org.springframework.web.method.annotation.RequestHeaderMapMethodArgumentResolver;
@@ -739,7 +738,7 @@ public class RequestMappingHandlerAdapter extends AbstractHandlerMethodAdapter
 		handlers.add(new AsyncTaskMethodReturnValueHandler(this.beanFactory));
 
 		// Annotation-based return value types
-		handlers.add(new ModelAttributeMethodProcessor(false));
+		handlers.add(new ServletModelAttributeMethodProcessor(false));
 		handlers.add(new RequestResponseBodyMethodProcessor(getMessageConverters(),
 				this.contentNegotiationManager, this.requestResponseBodyAdvice));
 
@@ -757,7 +756,7 @@ public class RequestMappingHandlerAdapter extends AbstractHandlerMethodAdapter
 			handlers.add(new ModelAndViewResolverMethodReturnValueHandler(getModelAndViewResolvers()));
 		}
 		else {
-			handlers.add(new ModelAttributeMethodProcessor(true));
+			handlers.add(new ServletModelAttributeMethodProcessor(true));
 		}
 
 		return handlers;

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/ServletModelAttributeMethodProcessor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -108,8 +108,8 @@ public class ServletModelAttributeMethodProcessor extends ModelAttributeMethodPr
 		return null;
 	}
 
-	@SuppressWarnings("unchecked")
 	protected final Map<String, String> getUriTemplateVariables(NativeWebRequest request) {
+		@SuppressWarnings("unchecked")
 		Map<String, String> variables = (Map<String, String>) request.getAttribute(
 				HandlerMapping.URI_TEMPLATE_VARIABLES_ATTRIBUTE, RequestAttributes.SCOPE_REQUEST);
 		return (variables != null ? variables : Collections.emptyMap());
@@ -158,4 +158,23 @@ public class ServletModelAttributeMethodProcessor extends ModelAttributeMethodPr
 		servletBinder.bind(servletRequest);
 	}
 
+	@Override
+	@Nullable
+	public Object resolveConstructorArgument(String paramName, Class<?> paramType, NativeWebRequest request)
+			throws Exception {
+
+		Object value = super.resolveConstructorArgument(paramName, paramType, request);
+		if (value != null) {
+			return value;
+		}
+		ServletRequest servletRequest = request.getNativeRequest(ServletRequest.class);
+		if (servletRequest != null) {
+			String attr = HandlerMapping.URI_TEMPLATE_VARIABLES_ATTRIBUTE;
+			@SuppressWarnings("unchecked")
+			Map<String, String> uriVars = (Map<String, String>) servletRequest.getAttribute(attr);
+			return uriVars.get(paramName);
+		}
+		return null;
+	}
+
 }

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

@@ -57,6 +57,7 @@ import javax.servlet.http.Cookie;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import javax.servlet.http.HttpSession;
+import javax.servlet.http.Part;
 import javax.validation.Valid;
 import javax.validation.constraints.NotNull;
 import javax.xml.bind.annotation.XmlRootElement;
@@ -108,6 +109,7 @@ import org.springframework.ui.Model;
 import org.springframework.ui.ModelMap;
 import org.springframework.util.Assert;
 import org.springframework.util.MultiValueMap;
+import org.springframework.util.StreamUtils;
 import org.springframework.util.StringUtils;
 import org.springframework.validation.BindingResult;
 import org.springframework.validation.Errors;
@@ -139,6 +141,7 @@ import org.springframework.web.context.request.NativeWebRequest;
 import org.springframework.web.context.request.WebRequest;
 import org.springframework.web.context.support.GenericWebApplicationContext;
 import org.springframework.web.method.support.HandlerMethodArgumentResolver;
+import org.springframework.web.multipart.MultipartFile;
 import org.springframework.web.multipart.support.StringMultipartFileEditor;
 import org.springframework.web.servlet.DispatcherServlet;
 import org.springframework.web.servlet.ModelAndView;
@@ -158,6 +161,7 @@ import org.springframework.web.testfixture.servlet.MockHttpServletRequest;
 import org.springframework.web.testfixture.servlet.MockHttpServletResponse;
 import org.springframework.web.testfixture.servlet.MockMultipartFile;
 import org.springframework.web.testfixture.servlet.MockMultipartHttpServletRequest;
+import org.springframework.web.testfixture.servlet.MockPart;
 import org.springframework.web.testfixture.servlet.MockServletConfig;
 import org.springframework.web.testfixture.servlet.MockServletContext;
 
@@ -1934,6 +1938,44 @@ public class ServletAnnotationControllerHandlerMethodTests extends AbstractServl
 		assertThat(response.getContentAsString()).isEqualTo("value1-true-0");
 	}
 
+	@PathPatternsParameterizedTest
+	void dataClassBindingWithPathVariable(boolean usePathPatterns) throws Exception {
+		initDispatcherServlet(PathVariableDataClassController.class, usePathPatterns);
+
+		MockHttpServletRequest request = new MockHttpServletRequest("GET", "/bind/true");
+		request.addParameter("param1", "value1");
+		MockHttpServletResponse response = new MockHttpServletResponse();
+		getServlet().service(request, response);
+		assertThat(response.getContentAsString()).isEqualTo("value1-true-0");
+	}
+
+	@PathPatternsParameterizedTest
+	void dataClassBindingWithMultipartFile(boolean usePathPatterns) throws Exception {
+		initDispatcherServlet(MultipartFileDataClassController.class, usePathPatterns);
+
+		MockMultipartHttpServletRequest request = new MockMultipartHttpServletRequest();
+		request.setRequestURI("/bind");
+		request.addFile(new MockMultipartFile("param1", "value1".getBytes(StandardCharsets.UTF_8)));
+		request.addParameter("param2", "true");
+		MockHttpServletResponse response = new MockHttpServletResponse();
+		getServlet().service(request, response);
+		assertThat(response.getContentAsString()).isEqualTo("value1-true-0");
+	}
+
+	@PathPatternsParameterizedTest
+	void dataClassBindingWithServletPart(boolean usePathPatterns) throws Exception {
+		initDispatcherServlet(ServletPartDataClassController.class, usePathPatterns);
+
+		MockHttpServletRequest request = new MockHttpServletRequest();
+		request.setContentType("multipart/form-data");
+		request.setRequestURI("/bind");
+		request.addPart(new MockPart("param1", "value1".getBytes(StandardCharsets.UTF_8)));
+		request.addParameter("param2", "true");
+		MockHttpServletResponse response = new MockHttpServletResponse();
+		getServlet().service(request, response);
+		assertThat(response.getContentAsString()).isEqualTo("value1-true-0");
+	}
+
 	@PathPatternsParameterizedTest
 	void dataClassBindingWithAdditionalSetter(boolean usePathPatterns) throws Exception {
 		initDispatcherServlet(DataClassController.class, usePathPatterns);
@@ -3831,6 +3873,15 @@ public class ServletAnnotationControllerHandlerMethodTests extends AbstractServl
 		}
 	}
 
+	@RestController
+	public static class PathVariableDataClassController {
+
+		@RequestMapping("/bind/{param2}")
+		public String handle(DataClass data) {
+			return data.param1 + "-" + data.param2 + "-" + data.param3;
+		}
+	}
+
 	@RestController
 	public static class ValidatedDataClassController {
 
@@ -3873,6 +3924,70 @@ public class ServletAnnotationControllerHandlerMethodTests extends AbstractServl
 		}
 	}
 
+	public static class MultipartFileDataClass {
+
+		@NotNull
+		public final MultipartFile param1;
+
+		public final boolean param2;
+
+		public int param3;
+
+		@ConstructorProperties({"param1", "param2", "optionalParam"})
+		public MultipartFileDataClass(MultipartFile param1, boolean p2, Optional<Integer> optionalParam) {
+			this.param1 = param1;
+			this.param2 = p2;
+			Assert.notNull(optionalParam, "Optional must not be null");
+			optionalParam.ifPresent(integer -> this.param3 = integer);
+		}
+
+		public void setParam3(int param3) {
+			this.param3 = param3;
+		}
+	}
+
+	@RestController
+	public static class MultipartFileDataClassController {
+
+		@RequestMapping("/bind")
+		public String handle(MultipartFileDataClass data) throws IOException {
+			return StreamUtils.copyToString(data.param1.getInputStream(), StandardCharsets.UTF_8) +
+					"-" + data.param2 + "-" + data.param3;
+		}
+	}
+
+	public static class ServletPartDataClass {
+
+		@NotNull
+		public final Part param1;
+
+		public final boolean param2;
+
+		public int param3;
+
+		@ConstructorProperties({"param1", "param2", "optionalParam"})
+		public ServletPartDataClass(Part param1, boolean p2, Optional<Integer> optionalParam) {
+			this.param1 = param1;
+			this.param2 = p2;
+			Assert.notNull(optionalParam, "Optional must not be null");
+			optionalParam.ifPresent(integer -> this.param3 = integer);
+		}
+
+		public void setParam3(int param3) {
+			this.param3 = param3;
+		}
+	}
+
+	@RestController
+	public static class ServletPartDataClassController {
+
+		@RequestMapping("/bind")
+		public String handle(ServletPartDataClass data) throws IOException {
+			return StreamUtils.copyToString(data.param1.getInputStream(), StandardCharsets.UTF_8) +
+					"-" + data.param2 + "-" + data.param3;
+		}
+	}
+
 	@RestController
 	public static class OptionalDataClassController {