From 0182dbf3c7b175f1532bbe4769e7d029ce24a800 Mon Sep 17 00:00:00 2001
From: Gerrit Meier <gerrit.meier@neo4j.com>
Date: Thu, 25 Jan 2018 13:15:53 +0100
Subject: [PATCH] DATAGRAPH-1064 - Instantiate OgmEntityInstantiator later.

Extract the instantiation of OgmEntityInstantiator after the mapping
context got created.
Do not require an existing ConversionService but instantiate a fallback
to MetaDataDrivenConversionService.

(cherry picked from commit 010e336)
---
 .../Neo4jMappingContextFactoryBean.java       | 22 ------------
 ...gmEntityInstantiatorConfigurationBean.java | 35 +++++++++++++++++++
 ...Neo4jRepositoryConfigurationExtension.java | 14 ++++++--
 3 files changed, 47 insertions(+), 24 deletions(-)
 create mode 100644 spring-data-neo4j/src/main/java/org/springframework/data/neo4j/repository/config/Neo4jOgmEntityInstantiatorConfigurationBean.java

diff --git a/spring-data-neo4j/src/main/java/org/springframework/data/neo4j/repository/config/Neo4jMappingContextFactoryBean.java b/spring-data-neo4j/src/main/java/org/springframework/data/neo4j/repository/config/Neo4jMappingContextFactoryBean.java
index 50f08b3c3..304cc8300 100644
--- a/spring-data-neo4j/src/main/java/org/springframework/data/neo4j/repository/config/Neo4jMappingContextFactoryBean.java
+++ b/spring-data-neo4j/src/main/java/org/springframework/data/neo4j/repository/config/Neo4jMappingContextFactoryBean.java
@@ -14,19 +14,13 @@
 package org.springframework.data.neo4j.repository.config;
 
 import org.neo4j.ogm.session.SessionFactory;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 import org.springframework.beans.BeansException;
-import org.springframework.beans.DirectFieldAccessor;
 import org.springframework.beans.factory.FactoryBean;
 import org.springframework.beans.factory.ListableBeanFactory;
-import org.springframework.beans.factory.NoSuchBeanDefinitionException;
 import org.springframework.beans.factory.config.AbstractFactoryBean;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.ApplicationContextAware;
-import org.springframework.core.convert.ConversionService;
 import org.springframework.data.neo4j.mapping.Neo4jMappingContext;
-import org.springframework.util.ClassUtils;
 
 /**
  * {@link FactoryBean} to setup {@link Neo4jMappingContext} instances from Spring configuration.
@@ -37,9 +31,6 @@ import org.springframework.util.ClassUtils;
 public class Neo4jMappingContextFactoryBean extends AbstractFactoryBean<Neo4jMappingContext> implements
 		ApplicationContextAware {
 
-	private static final Logger LOG = LoggerFactory.getLogger(Neo4jMappingContextFactoryBean.class);
-	private static final boolean HAS_ENTITY_INSTANTIATOR_FEATURE = ClassUtils.isPresent("org.neo4j.ogm.session.EntityInstantiator",
-			Neo4jMappingContextFactoryBean.class.getClassLoader());
 	private ListableBeanFactory beanFactory;
 
 	/*
@@ -66,22 +57,9 @@ public class Neo4jMappingContextFactoryBean extends AbstractFactoryBean<Neo4jMap
 	 */
 	@Override
 	protected Neo4jMappingContext createInstance() {
-
 		SessionFactory sessionFactory = beanFactory.getBean(SessionFactory.class);
 		Neo4jMappingContext context = new Neo4jMappingContext(sessionFactory.metaData());
 		context.initialize();
-
-		if (HAS_ENTITY_INSTANTIATOR_FEATURE) {
-			ConversionService conversionService = null;
-			try {
-				conversionService = beanFactory.getBean(ConversionService.class);
-			} catch (NoSuchBeanDefinitionException e) {
-				LOG.debug("Unable to find a conversion service to use for entity instantiation, using none");
-			}
-			new DirectFieldAccessor(sessionFactory).setPropertyValue("entityInstantiator",
-					new OgmEntityInstantiatorAdapter(context, conversionService));
-		}
-
 		return context;
 	}
 
diff --git a/spring-data-neo4j/src/main/java/org/springframework/data/neo4j/repository/config/Neo4jOgmEntityInstantiatorConfigurationBean.java b/spring-data-neo4j/src/main/java/org/springframework/data/neo4j/repository/config/Neo4jOgmEntityInstantiatorConfigurationBean.java
new file mode 100644
index 000000000..7a6e93901
--- /dev/null
+++ b/spring-data-neo4j/src/main/java/org/springframework/data/neo4j/repository/config/Neo4jOgmEntityInstantiatorConfigurationBean.java
@@ -0,0 +1,35 @@
+package org.springframework.data.neo4j.repository.config;
+
+import org.neo4j.ogm.session.SessionFactory;
+import org.springframework.beans.factory.InitializingBean;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.core.convert.ConversionService;
+import org.springframework.data.neo4j.conversion.MetaDataDrivenConversionService;
+import org.springframework.data.neo4j.mapping.Neo4jMappingContext;
+
+public class Neo4jOgmEntityInstantiatorConfigurationBean implements InitializingBean {
+
+	private final SessionFactory sessionFactory;
+	private final Neo4jMappingContext mappingContext;
+	private ConversionService conversionService;
+
+	@Autowired
+	public Neo4jOgmEntityInstantiatorConfigurationBean(SessionFactory sessionFactory, Neo4jMappingContext mappingContext) {
+		this.sessionFactory = sessionFactory;
+		this.mappingContext = mappingContext;
+	}
+
+	@Override
+	public void afterPropertiesSet() {
+		sessionFactory.setEntityInstantiator(
+				new OgmEntityInstantiatorAdapter(
+						mappingContext,
+						conversionService != null ? conversionService : new MetaDataDrivenConversionService(sessionFactory.metaData()))
+		);
+	}
+
+	@Autowired(required = false)
+	public void setConversionService(ConversionService conversionService) {
+		this.conversionService = conversionService;
+	}
+}
diff --git a/spring-data-neo4j/src/main/java/org/springframework/data/neo4j/repository/config/Neo4jRepositoryConfigurationExtension.java b/spring-data-neo4j/src/main/java/org/springframework/data/neo4j/repository/config/Neo4jRepositoryConfigurationExtension.java
index b261c3596..33aba9a32 100644
--- a/spring-data-neo4j/src/main/java/org/springframework/data/neo4j/repository/config/Neo4jRepositoryConfigurationExtension.java
+++ b/spring-data-neo4j/src/main/java/org/springframework/data/neo4j/repository/config/Neo4jRepositoryConfigurationExtension.java
@@ -20,7 +20,8 @@ import java.util.Optional;
 
 import org.neo4j.ogm.annotation.NodeEntity;
 import org.neo4j.ogm.annotation.RelationshipEntity;
-
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.support.BeanDefinitionBuilder;
 import org.springframework.beans.factory.support.BeanDefinitionRegistry;
 import org.springframework.beans.factory.support.RootBeanDefinition;
@@ -34,6 +35,7 @@ import org.springframework.data.repository.config.AnnotationRepositoryConfigurat
 import org.springframework.data.repository.config.RepositoryConfigurationExtensionSupport;
 import org.springframework.data.repository.config.RepositoryConfigurationSource;
 import org.springframework.data.repository.config.XmlRepositoryConfigurationSource;
+import org.springframework.util.ClassUtils;
 import org.springframework.util.StringUtils;
 
 /**
@@ -50,9 +52,11 @@ public class Neo4jRepositoryConfigurationExtension extends RepositoryConfigurati
 
 	private static final String DEFAULT_TRANSACTION_MANAGER_BEAN_NAME = "transactionManager";
 	private static final String NEO4J_MAPPING_CONTEXT_BEAN_NAME = "neo4jMappingContext";
+	private static final String NEO4J_ENTITY_INSTANTIATOR_CONFIGURATION_BEAN_NAME = "neo4jOgmEntityInstantiatorConfigurationBean";
 	private static final String ENABLE_DEFAULT_TRANSACTIONS_ATTRIBUTE = "enableDefaultTransactions";
 	private static final String SESSION_BEAN_DEFINITION_REGISTRAR_POST_PROCESSOR_BEAN_NAME = "sessionBeanDefinitionRegistrarPostProcessor";
-
+	private static final boolean HAS_ENTITY_INSTANTIATOR_FEATURE = ClassUtils.isPresent("org.neo4j.ogm.session.EntityInstantiator",
+			Neo4jMappingContextFactoryBean.class.getClassLoader());
 	/*
 	 * (non-Javadoc)
 	 * @see org.springframework.data.repository.config.RepositoryConfigurationExtensionSupport#getModuleName()
@@ -159,5 +163,11 @@ public class Neo4jRepositoryConfigurationExtension extends RepositoryConfigurati
 
 		registerIfNotAlreadyRegistered(new RootBeanDefinition(Neo4jMappingContextFactoryBean.class), registry,
 				NEO4J_MAPPING_CONTEXT_BEAN_NAME, source);
+
+		if (HAS_ENTITY_INSTANTIATOR_FEATURE) {
+			registerIfNotAlreadyRegistered(new RootBeanDefinition(Neo4jOgmEntityInstantiatorConfigurationBean.class),
+					registry, NEO4J_ENTITY_INSTANTIATOR_CONFIGURATION_BEAN_NAME, source);
+		}
+
 	}
 }