DATADOC-259 - MappingMongoConverter now converts Maps nested in Collections as well.

Fixed nested type handling in MappingMongoConverter.writeMapInternally(…). Force usage of ConversionService for simple values if read value doesn't match target type.

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/MappingMongoConverter.java

@@ -69,14 +69,12 @@ import org.springframework.util.StringUtils;
  * {@link MongoConverter} that uses a {@link MappingContext} to do sophisticated mapping of domain objects to
  * {@link DBObject}.
  * 
- * @author Jon Brisbin <jbrisbin@vmware.com>
  * @author Oliver Gierke
+ * @author Jon Brisbin
  */
 public class MappingMongoConverter extends AbstractMongoConverter implements ApplicationContextAware,
 		TypeMapperProvider {
 
-	@SuppressWarnings("rawtypes")
-	private static final TypeInformation<Map> MAP_TYPE_INFORMATION = ClassTypeInformation.from(Map.class);
 	private static final List<Class<?>> VALID_ID_TYPES = Arrays.asList(new Class<?>[] { ObjectId.class, String.class,
 			BigInteger.class, byte[].class });
 
@@ -545,8 +543,7 @@ public class MappingMongoConverter extends AbstractMongoConverter implements App
 				dbList.add(createCollectionDBObject(asCollection(element), componentType));
 			} else {
 				BasicDBObject propDbObj = new BasicDBObject();
-				writeInternal(element, propDbObj,
-						mappingContext.getPersistentEntity(ClassTypeInformation.from(element.getClass())));
+				writeInternal(element, propDbObj);
 				addCustomTypeKeyIfNecessary(componentType, element, propDbObj);
 				dbList.add(propDbObj);
 			}
@@ -645,10 +642,8 @@ public class MappingMongoConverter extends AbstractMongoConverter implements App
 	@SuppressWarnings({ "rawtypes", "unchecked" })
 	private Object getPotentiallyConvertedSimpleRead(Object value, Class<?> target) {
 
-		Assert.notNull(target);
-
-		if (value == null) {
-			return null;
+		if (value == null || target == null) {
+			return value;
 		}
 
 		if (conversions.hasCustomReadTarget(value.getClass(), target)) {
@@ -658,8 +653,8 @@ public class MappingMongoConverter extends AbstractMongoConverter implements App
 		if (target.isEnum()) {
 			return Enum.valueOf((Class<Enum>) target, value.toString());
 		}
-
-		return value;
+		
+		return target.isAssignableFrom(value.getClass()) ? value : conversionService.convert(value, target);
 	}
 
 	protected DBRef createDBRef(Object target, org.springframework.data.mongodb.core.mapping.DBRef dbref) {
@@ -810,8 +805,8 @@ public class MappingMongoConverter extends AbstractMongoConverter implements App
 			if (value instanceof DBObject) {
 				map.put(key, read(valueType, (DBObject) value));
 			} else {
-				valueType = valueType == null ? MAP_TYPE_INFORMATION : valueType;
-				map.put(key, getPotentiallyConvertedSimpleRead(value, valueType.getType()));
+				Class<?> valueClass = valueType == null ? null : valueType.getType();
+				map.put(key, getPotentiallyConvertedSimpleRead(value, valueClass));
 			}
 		}
 

spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/convert/MappingMongoConverterUnitTests.java

@@ -666,6 +666,51 @@ public class MappingMongoConverterUnitTests {
 		assertThat(doublyNestedObject, is(instanceOf(Map.class)));
 		assertThat((String) ((Map<?, ?>) doublyNestedObject).get("Hello"), is(equalTo("World")));
 	}
+	
+	/**
+	 * @see DATADOC-259
+	 */
+	@Test
+	public void writesListOfMapsCorrectly() {
+		
+		Map<String, Locale> map = Collections.singletonMap("Foo", Locale.ENGLISH);
+		
+		CollectionWrapper wrapper = new CollectionWrapper();
+		wrapper.listOfMaps = new ArrayList<Map<String,Locale>>();
+		wrapper.listOfMaps.add(map);
+		
+		DBObject result = new BasicDBObject();
+		converter.write(wrapper, result);
+		
+		BasicDBList list = (BasicDBList) result.get("listOfMaps");
+		assertThat(list, is(notNullValue()));
+		assertThat(list.size(), is(1));
+		
+		DBObject dbObject = (DBObject) list.get(0);
+		assertThat(dbObject.containsField("Foo"), is(true));
+		assertThat((String) dbObject.get("Foo"), is(Locale.ENGLISH.toString()));
+	}
+	
+	/**
+	 * @see DATADOC-259
+	 */
+	@Test
+	public void readsListOfMapsCorrectly() {
+		
+		DBObject map = new BasicDBObject("Foo", "en");
+		
+		BasicDBList list = new BasicDBList();
+		list.add(map);
+		
+		DBObject wrapperSource = new BasicDBObject("listOfMaps", list);
+		
+		CollectionWrapper wrapper = converter.read(CollectionWrapper.class, wrapperSource);
+		
+		assertThat(wrapper.listOfMaps, is(notNullValue()));
+		assertThat(wrapper.listOfMaps.size(), is(1));
+		assertThat(wrapper.listOfMaps.get(0), is(notNullValue()));
+		assertThat(wrapper.listOfMaps.get(0).get("Foo"), is(Locale.ENGLISH));
+	}
 
 	class GenericType<T> {
 		T content;
@@ -735,6 +780,7 @@ public class MappingMongoConverterUnitTests {
 	class CollectionWrapper {
 		List<Contact> contacts;
 		List<List<String>> strings;
+		List<Map<String, Locale>> listOfMaps;
 	}
 
 	class LocaleWrapper {