From e1daf36ed82407f680e7b7c4777e0bc3daf593f8 Mon Sep 17 00:00:00 2001
From: Oliver Gierke <info@olivergierke.de>
Date: Fri, 22 Jul 2011 17:52:48 +0200
Subject: [PATCH] DATADOC-209 - MappingMongoConverter handles collections of
 enums correctly now.

---
 .../core/convert/MappingMongoConverter.java   | 51 ++++++++++++++++---
 .../MappingMongoConverterUnitTests.java       | 37 ++++++++++++++
 2 files changed, 82 insertions(+), 6 deletions(-)

diff --git a/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/MappingMongoConverter.java b/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/MappingMongoConverter.java
index 2fa85870b..77b247005 100644
--- a/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/MappingMongoConverter.java
+++ b/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/MappingMongoConverter.java
@@ -535,7 +535,7 @@ public class MappingMongoConverter extends AbstractMongoConverter implements App
 			Class<?> elementType = element.getClass();
 
 			if (conversions.isSimpleType(elementType)) {
-				dbList.add(element);
+				dbList.add(getPotentiallyConvertedSimpleWrite(element));
 			} else if (element instanceof Collection || elementType.isArray()) {
 				dbList.add(createCollectionDBObject(componentType, asCollection(element)));
 			} else {
@@ -601,16 +601,55 @@ public class MappingMongoConverter extends AbstractMongoConverter implements App
 	 * @param dbObject
 	 */
 	private void writeSimpleInternal(String key, Object value, DBObject dbObject) {
+		dbObject.put(key, getPotentiallyConvertedSimpleWrite(value));
+	}
 
+	/**
+	 * Checks whether we have a custom conversion registered for the given value into an arbitrary simple Mongo type.
+	 * Returns the converted value if so. If not, we perform special enum handling or simply return the value as is.
+	 * 
+	 * @param value
+	 * @return
+	 */
+	private Object getPotentiallyConvertedSimpleWrite(Object value) {
+		
+		if (value == null) {
+			return null;
+		}
+		
 		Class<?> customTarget = conversions.getCustomWriteTarget(value.getClass(), null);
 
-		Object valueToSet = null;
 		if (customTarget != null) {
-			valueToSet = conversionService.convert(value, customTarget);
+			return conversionService.convert(value, customTarget);
 		} else {
-			valueToSet = value.getClass().isEnum() ? ((Enum<?>) value).name() : value;
+			return value.getClass().isEnum() ? ((Enum<?>) value).name() : value;
 		}
-		dbObject.put(key, valueToSet);
+	}
+	
+	/**
+	 * Checks whether we have a custom conversion for the given simple object. Converts the given value if so, applies
+	 * {@link Enum} handling or returns the value as is.
+	 * 
+	 * @param value
+	 * @param target must not be {@literal null}.
+	 * @return
+	 */
+	@SuppressWarnings({ "rawtypes", "unchecked" })
+	private Object getPotentiallyConvertedSimpleRead(Object value, Class<?> target) {
+		
+		if (value == null) {
+			return null;
+		}
+		
+		if (conversions.hasCustomReadTarget(value.getClass(), target)) {
+			return conversionService.convert(value, target);
+		}
+		
+		if (target.isEnum()) {
+			return Enum.valueOf((Class<Enum>) target, value.toString());
+		}
+		
+		return value;
 	}
 
 	protected DBRef createDBRef(Object target, org.springframework.data.mongodb.core.mapping.DBRef dbref) {
@@ -686,7 +725,7 @@ public class MappingMongoConverter extends AbstractMongoConverter implements App
 						} else if (dbObjItem instanceof DBObject) {
 							items.add(read(prop.getComponentType(), (DBObject) dbObjItem));
 						} else {
-							items.add(dbObjItem);
+							items.add(getPotentiallyConvertedSimpleRead(dbObjItem, prop.getComponentType()));
 						}
 					}
 
diff --git a/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/convert/MappingMongoConverterUnitTests.java b/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/convert/MappingMongoConverterUnitTests.java
index c38b4c37d..ab0f601e2 100644
--- a/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/convert/MappingMongoConverterUnitTests.java
+++ b/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/convert/MappingMongoConverterUnitTests.java
@@ -196,6 +196,25 @@ public class MappingMongoConverterUnitTests {
 		assertThat(result.get("sampleEnum").toString(), is("FIRST"));
 	}
 	
+	/**
+	 * @see DATADOC-209
+	 */
+	@Test
+	public void writesEnumCollectionCorrectly() {
+		
+		ClassWithEnumProperty value = new ClassWithEnumProperty();
+		value.enums = Arrays.asList(SampleEnum.FIRST);
+		
+		DBObject result = new BasicDBObject();
+		converter.write(value, result);
+		
+		assertThat(result.get("enums"), is(BasicDBList.class));
+		
+		BasicDBList enums = (BasicDBList) result.get("enums");
+		assertThat(enums.size(), is(1));
+		assertThat((String) enums.get(0), is("FIRST"));
+	}
+	
 	/**
 	 * @see DATADOC-136
 	 */
@@ -207,6 +226,23 @@ public class MappingMongoConverterUnitTests {
 		assertThat(result.sampleEnum, is(SampleEnum.FIRST));
 	}
 	
+	/**
+	 * @see DATADOC-209
+	 */
+	@Test
+	public void readsEnumCollectionsCorrectly() {
+		
+		BasicDBList enums = new BasicDBList();
+		enums.add("FIRST");
+		DBObject dbObject = new BasicDBObject("enums", enums);
+		
+		ClassWithEnumProperty result = converter.read(ClassWithEnumProperty.class, dbObject);
+		
+		assertThat(result.enums, is(List.class));
+		assertThat(result.enums.size(), is(1));
+		assertThat(result.enums, hasItem(SampleEnum.FIRST));
+	}
+	
 	/**
 	 * @see DATADOC-144
 	 */
@@ -415,6 +451,7 @@ public class MappingMongoConverterUnitTests {
 	class ClassWithEnumProperty {
 		
 		SampleEnum sampleEnum;
+		List<SampleEnum> enums;
 	}
 	
 	enum SampleEnum {