DATAMONGO-1001 - Fix saving lazy loaded object.

We now resolve the target type for CGLib-proxied objects and initialize lazy loaded ones before saving. As it turns out CustomConversions already knows how to deal with proxies correctly. Ee added an explicit test to assert that.

Original pull request: #208.

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

@@ -56,6 +56,7 @@ import org.springframework.data.util.ClassTypeInformation;
 import org.springframework.data.util.TypeInformation;
 import org.springframework.expression.spel.standard.SpelExpressionParser;
 import org.springframework.util.Assert;
+import org.springframework.util.ClassUtils;
 import org.springframework.util.CollectionUtils;
 
 import com.mongodb.BasicDBList;
@@ -315,14 +316,17 @@ public class MappingMongoConverter extends AbstractMongoConverter implements App
 			return;
 		}
 
-		boolean handledByCustomConverter = conversions.getCustomWriteTarget(obj.getClass(), DBObject.class) != null;
-		TypeInformation<? extends Object> type = ClassTypeInformation.from(obj.getClass());
+		Class<?> entityType = obj.getClass();
+		boolean handledByCustomConverter = conversions.getCustomWriteTarget(entityType, DBObject.class) != null;
+		TypeInformation<? extends Object> type = ClassTypeInformation.from(entityType);
 
 		if (!handledByCustomConverter && !(dbo instanceof BasicDBList)) {
 			typeMapper.writeType(type, dbo);
 		}
 
-		writeInternal(obj, dbo, type);
+		Object target = obj instanceof LazyLoadingProxy ? ((LazyLoadingProxy) obj).getTarget() : obj;
+
+		writeInternal(target, dbo, type);
 	}
 
 	/**
@@ -338,7 +342,8 @@ public class MappingMongoConverter extends AbstractMongoConverter implements App
 			return;
 		}
 
-		Class<?> customTarget = conversions.getCustomWriteTarget(obj.getClass(), DBObject.class);
+		Class<?> entityType = obj.getClass();
+		Class<?> customTarget = conversions.getCustomWriteTarget(entityType, DBObject.class);
 
 		if (customTarget != null) {
 			DBObject result = conversionService.convert(obj, DBObject.class);
@@ -346,17 +351,17 @@ public class MappingMongoConverter extends AbstractMongoConverter implements App
 			return;
 		}
 
-		if (Map.class.isAssignableFrom(obj.getClass())) {
+		if (Map.class.isAssignableFrom(entityType)) {
 			writeMapInternal((Map<Object, Object>) obj, dbo, ClassTypeInformation.MAP);
 			return;
 		}
 
-		if (Collection.class.isAssignableFrom(obj.getClass())) {
+		if (Collection.class.isAssignableFrom(entityType)) {
 			writeCollectionInternal((Collection<?>) obj, ClassTypeInformation.LIST, (BasicDBList) dbo);
 			return;
 		}
 
-		MongoPersistentEntity<?> entity = mappingContext.getPersistentEntity(obj.getClass());
+		MongoPersistentEntity<?> entity = mappingContext.getPersistentEntity(entityType);
 		writeInternal(obj, dbo, entity);
 		addCustomTypeKeyIfNecessary(typeHint, obj, dbo);
 	}
@@ -463,7 +468,7 @@ public class MappingMongoConverter extends AbstractMongoConverter implements App
 		 * If we have a LazyLoadingProxy we make sure it is initialized first.
 		 */
 		if (obj instanceof LazyLoadingProxy) {
-			obj = ((LazyLoadingProxy) obj).initialize();
+			obj = ((LazyLoadingProxy) obj).getTarget();
 		}
 
 		// Lookup potential custom target type
@@ -683,10 +688,11 @@ public class MappingMongoConverter extends AbstractMongoConverter implements App
 
 		TypeInformation<?> actualType = type != null ? type.getActualType() : null;
 		Class<?> reference = actualType == null ? Object.class : actualType.getType();
+		Class<?> valueType = ClassUtils.getUserClass(value.getClass());
 
-		boolean notTheSameClass = !value.getClass().equals(reference);
+		boolean notTheSameClass = !valueType.equals(reference);
 		if (notTheSameClass) {
-			typeMapper.writeType(value.getClass(), dbObject);
+			typeMapper.writeType(valueType, dbObject);
 		}
 	}
 

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

@@ -2511,6 +2511,37 @@ public class MongoTemplateTests {
 		assertThat(template.getDb().getCollection("sample").find(new BasicDBObject("field", "data")).count(), is(1));
 	}
 
+	/**
+	 * @see DATAMONGO-1001
+	 */
+	@Test
+	public void shouldAllowSavingOfLazyLoadedDbRefs() {
+
+		template.dropCollection(SomeTemplate.class);
+		template.dropCollection(SomeMessage.class);
+		template.dropCollection(SomeContent.class);
+
+		SomeContent content = new SomeContent();
+		content.id = "content-1";
+		content.text = "spring";
+		template.save(content);
+
+		SomeTemplate tmpl = new SomeTemplate();
+		tmpl.id = "template-1";
+		tmpl.content = content; // @DBRef(lazy=true) tmpl.content
+
+		template.save(tmpl);
+
+		SomeTemplate savedTmpl = template.findById(tmpl.id, SomeTemplate.class);
+
+		SomeContent loadedContent = savedTmpl.getContent();
+		loadedContent.setText("data");
+		template.save(loadedContent);
+
+		assertThat(template.findById(content.id, SomeContent.class).getText(), is("data"));
+
+	}
+
 	/**
 	 * @see DATAMONGO-880
 	 */
@@ -2956,6 +2987,11 @@ public class MongoTemplateTests {
 			return name;
 		}
 
+		public void setText(String text) {
+			this.text = text;
+
+		}
+
 		public String getId() {
 			return id;
 		}

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

@@ -1,3 +1,18 @@
+/*
+ * Copyright 2011-2014 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
+ *
+ *      http://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.data.mongodb.core.convert;
 
 import static org.hamcrest.Matchers.*;
@@ -15,6 +30,7 @@ import org.bson.types.Binary;
 import org.bson.types.ObjectId;
 import org.joda.time.DateTime;
 import org.junit.Test;
+import org.springframework.aop.framework.ProxyFactory;
 import org.springframework.core.convert.converter.Converter;
 import org.springframework.core.convert.support.DefaultConversionService;
 import org.springframework.core.convert.support.GenericConversionService;
@@ -26,6 +42,7 @@ import com.mongodb.DBRef;
  * Unit tests for {@link CustomConversions}.
  * 
  * @author Oliver Gierke
+ * @auhtor Christoph Strobl
  */
 public class CustomConversionsUnitTests {
 
@@ -197,6 +214,35 @@ public class CustomConversionsUnitTests {
 		assertThat(conversionService.convert(new DateTime(), Date.class), is(new Date(0)));
 	}
 
+	/**
+	 * @see DATAMONGO-1001
+	 */
+	@Test
+	public void shouldSelectPropertCustomWriteTargetForCglibProxiedType() {
+
+		CustomConversions conversions = new CustomConversions(Arrays.asList(FormatToStringConverter.INSTANCE));
+		assertThat(conversions.getCustomWriteTarget(createProxyTypeFor(Format.class)), is(typeCompatibleWith(String.class)));
+	}
+
+	/**
+	 * @see DATAMONGO-1001
+	 */
+	@Test
+	public void shouldSelectPropertCustomReadTargetForCglibProxiedType() {
+
+		CustomConversions conversions = new CustomConversions(Arrays.asList(CustomObjectToStringConverter.INSTANCE));
+		assertThat(conversions.hasCustomReadTarget(createProxyTypeFor(Object.class), String.class), is(true));
+	}
+
+	private static Class<?> createProxyTypeFor(Class<?> type) {
+
+		ProxyFactory factory = new ProxyFactory();
+		factory.setProxyTargetClass(true);
+		factory.setTargetClass(type);
+
+		return factory.getProxy().getClass();
+	}
+
 	enum FormatToStringConverter implements Converter<Format, String> {
 		INSTANCE;
 
@@ -251,4 +297,15 @@ public class CustomConversionsUnitTests {
 			return new Date(0);
 		}
 	}
+
+	enum CustomObjectToStringConverter implements Converter<Object, String> {
+
+		INSTANCE;
+
+		@Override
+		public String convert(Object source) {
+			return source != null ? source.toString() : null;
+		}
+
+	}
 }

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

@@ -49,6 +49,7 @@ import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.mockito.Mock;
 import org.mockito.runners.MockitoJUnitRunner;
+import org.springframework.aop.framework.ProxyFactory;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.context.ApplicationContext;
 import org.springframework.core.convert.converter.Converter;
@@ -1834,6 +1835,37 @@ public class MappingMongoConverterUnitTests {
 		assertThat(entity.score, equalTo(5F));
 	}
 
+	/**
+	 * @see DATAMONGO-1001
+	 */
+	@Test
+	public void shouldWriteCglibProxiedClassTypeInformationCorrectly() {
+
+		ProxyFactory factory = new ProxyFactory();
+		factory.setTargetClass(GenericType.class);
+		factory.setProxyTargetClass(true);
+
+		GenericType<?> proxied = (GenericType<?>) factory.getProxy();
+		BasicDBObject dbo = new BasicDBObject();
+		converter.write(proxied, dbo);
+
+		assertThat(dbo.get("_class"), is((Object) GenericType.class.getName()));
+	}
+
+	/**
+	 * @see DATAMONGO-1001
+	 */
+	@Test
+	public void shouldUseTargetObjectOfLazyLoadingProxyWhenWriting() {
+
+		LazyLoadingProxy mock = mock(LazyLoadingProxy.class);
+
+		BasicDBObject dbo = new BasicDBObject();
+		converter.write(mock, dbo);
+
+		verify(mock, times(1)).getTarget();
+	}
+
 	static class GenericType<T> {
 		T content;
 	}