From 779d9d6a79264de45a16182a319053517087dd10 Mon Sep 17 00:00:00 2001
From: Oliver Gierke <info@olivergierke.de>
Date: Tue, 8 Mar 2011 14:32:34 +0100
Subject: [PATCH] Extended SimpleMongoConverter to support registering custom
 types.

Values of the registered custom types are serialized using the underlying ConversionService. This way we can plug in custom converters, e.g. for JodaTime and the like.
---
 .../mongodb/SimpleMongoConverter.java         | 36 ++++++++++++-------
 1 file changed, 24 insertions(+), 12 deletions(-)

diff --git a/spring-data-mongodb/src/main/java/org/springframework/data/document/mongodb/SimpleMongoConverter.java b/spring-data-mongodb/src/main/java/org/springframework/data/document/mongodb/SimpleMongoConverter.java
index 7a9fdc9e7..74377ef68 100644
--- a/spring-data-mongodb/src/main/java/org/springframework/data/document/mongodb/SimpleMongoConverter.java
+++ b/spring-data-mongodb/src/main/java/org/springframework/data/document/mongodb/SimpleMongoConverter.java
@@ -116,14 +116,14 @@ public class SimpleMongoConverter implements MongoConverter {
 		SIMPLE_TYPES = Collections.unmodifiableSet(basics);
 	}
 
+	private final Set<String> customTypes;
 	private final GenericConversionService conversionService;
 
 	/**
 	 * Creates a {@link SimpleMongoConverter}.
 	 */
 	public SimpleMongoConverter() {
-		this.conversionService = ConversionServiceFactory.createDefaultConversionService();
-		initializeConverters();
+		this(ConversionServiceFactory.createDefaultConversionService());
 	}
 
 	/**
@@ -132,8 +132,21 @@ public class SimpleMongoConverter implements MongoConverter {
 	 * @param conversionService
 	 */
 	public SimpleMongoConverter(GenericConversionService conversionService) {
+		this(conversionService, new HashSet<String>());
+	}
+
+	/**
+	 * Creates a new {@link SimpleMongoConverter} for the given {@link ConversionService} and custom types. The custom
+	 * types will not be traversed during writing but rather serialized using the given {@link ConversionService}.
+	 * 
+	 * @param conversionService
+	 * @param customTypes
+	 */
+	public SimpleMongoConverter(GenericConversionService conversionService, Set<String> customTypes) {
+
 		Assert.notNull(conversionService);
 		this.conversionService = conversionService;
+		this.customTypes = customTypes;
 		initializeConverters();
 	}
 
@@ -142,12 +155,10 @@ public class SimpleMongoConverter implements MongoConverter {
 	 * id types if none are registered for those conversion already. {@link GenericConversionService} is configured.
 	 */
 	protected void initializeConverters() {
-		
-		if (!conversionService.canConvert(ObjectId.class, String.class)) {
-			conversionService.addConverter(ObjectIdToStringConverter.INSTANCE);
-			conversionService.addConverter(StringToObjectIdConverter.INSTANCE);
-		}
-		
+
+		conversionService.addConverter(ObjectIdToStringConverter.INSTANCE);
+		conversionService.addConverter(StringToObjectIdConverter.INSTANCE);
+
 		if (!conversionService.canConvert(ObjectId.class, BigInteger.class)) {
 			conversionService.addConverter(ObjectIdToBigIntegerConverter.INSTANCE);
 			conversionService.addConverter(BigIntegerToIdConverter.INSTANCE);
@@ -176,18 +187,19 @@ public class SimpleMongoConverter implements MongoConverter {
 				if (descriptor.isEnum()) {
 					writeValue(dbo, keyToUse, ((Enum) value).name());
 				} else if (descriptor.isIdProperty() && descriptor.isOfIdType()) {
-					if (value instanceof String && ObjectId.isValid((String)value)) {
+					if (value instanceof ObjectId || value instanceof String && ObjectId.isValid((String) value)) {
 						try {
 							writeValue(dbo, keyToUse, conversionService.convert(value, ObjectId.class));
 						} catch (ConversionFailedException iae) {
 							LOG.warn("Unable to convert the String " + value + " to an ObjectId");
 							writeValue(dbo, keyToUse, value);
 						}
-					}
-					else {
+					} else {
 						// we can't convert this id - use as is
 						writeValue(dbo, keyToUse, value);
 					}
+				} else if (customTypes.contains(descriptor.getPropertyType().getName())) {
+					writeValue(dbo, keyToUse, conversionService.convert(value, String.class));
 				} else {
 					writeValue(dbo, keyToUse, value);
 				}
@@ -438,7 +450,7 @@ public class SimpleMongoConverter implements MongoConverter {
 		return map;
 	}
 
-	protected static boolean isSimpleType(Class<?> propertyType) {
+	private static boolean isSimpleType(Class<?> propertyType) {
 		if (propertyType == null) {
 			return false;
 		}