sp7839 - map autogrow, including auto-grow support for map values

org.springframework.beans/src/main/java/org/springframework/beans/BeanWrapperImpl.java

@@ -603,7 +603,7 @@ public class BeanWrapperImpl extends AbstractPropertyAccessor implements BeanWra
 	}
 	
 	private PropertyValue createDefaultPropertyValue(PropertyTokenHolder tokens) {
-		Class type = getPropertyType(tokens.canonicalName);
+		Class<?> type = getPropertyTypeDescriptor(tokens.canonicalName).getType();
 		if (type == null) {
 			throw new NullValueInNestedPathException(getRootClass(), this.nestedPath + tokens.canonicalName,
 					"Could not determine property type for auto-growing a default value");
@@ -637,6 +637,7 @@ public class BeanWrapperImpl extends AbstractPropertyAccessor implements BeanWra
 			}
 		}
 		catch (Exception ex) {
+			// TODO Root cause exception context is lost here... should we throw another exception type that preserves context instead?
 			throw new NullValueInNestedPathException(getRootClass(), this.nestedPath + name,
 					"Could not instantiate property type [" + type.getName() + "] to auto-grow nested property path: " + ex);
 		}
@@ -936,11 +937,20 @@ public class BeanWrapperImpl extends AbstractPropertyAccessor implements BeanWra
 			// Set value for last key.
 			String key = tokens.keys[tokens.keys.length - 1];
 			if (propValue == null) {
-				throw new NullValueInNestedPathException(getRootClass(), this.nestedPath + propertyName,
-						"Cannot access indexed value in property referenced " +
-						"in indexed property path '" + propertyName + "': returned null");
+				// null map value case
+				if (this.autoGrowNestedPaths) {
+					// TODO: cleanup, this is pretty hacky
+					int lastKeyIndex = tokens.canonicalName.lastIndexOf('[');
+					getterTokens.canonicalName = tokens.canonicalName.substring(0, lastKeyIndex);
+					propValue = setDefaultValue(getterTokens);
+				}
+				else {
+					throw new NullValueInNestedPathException(getRootClass(), this.nestedPath + propertyName,
+							"Cannot access indexed value in property referenced " +
+							"in indexed property path '" + propertyName + "': returned null");
+				}
 			}
-			else if (propValue.getClass().isArray()) {
+			if (propValue.getClass().isArray()) {
 				PropertyDescriptor pd = getCachedIntrospectionResults().getPropertyDescriptor(actualName);
 				Class requiredType = propValue.getClass().getComponentType();
 				int arrayIndex = Integer.parseInt(key);

org.springframework.web.servlet/src/test/java/org/springframework/web/servlet/mvc/annotation/Spr7839Tests.java

@@ -2,8 +2,6 @@ package org.springframework.web.servlet.mvc.annotation;
 
 import static org.junit.Assert.assertEquals;
 
-import java.util.ArrayList;
-import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
@@ -101,7 +99,6 @@ public class Spr7839Tests {
 	}
 
 	@Test
-	@Ignore
 	public void map() throws Exception {
 		request.setRequestURI("/nested/map");		
 		request.addParameter("nested.map['apple'].foo", "bar");
@@ -185,12 +182,12 @@ public class Spr7839Tests {
 
 	    private List<NestedBean>[] arrayOfLists;
 
-	    private Map<String, NestedBean> map = new HashMap<String, NestedBean>();
+	    private Map<String, NestedBean> map;
 
-	    private Map<String, List<Integer>> mapOfLists = new HashMap<String, List<Integer>>();
+	    private Map<String, List<Integer>> mapOfLists;
 	    
 	    public NestedBean() {
-	    	mapOfLists.put("apples", new ArrayList<Integer>());
+	    	
 	    }
 	    
 	    public NestedBean(String foo) {