From 9ce8d958e7838cc4cf39f89f1e2584e58813665e Mon Sep 17 00:00:00 2001
From: Oliver Gierke <ogierke@pivotal.io>
Date: Thu, 17 May 2018 15:10:33 +0200
Subject: [PATCH] DATAJPA-1347 - Added Hibernate-specific ProxyDetector.
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This allows us to properly detect Hibernate 5.3 proxies. That version changed the proxy class names being generated in a way that Spring's own ClassUtils.getUserClass(…) doesn't properly return the actual target class anymore. We now build on the infrastructure introduced in DATACMNS-1324 and explicitly check for Hibernate's HibernateProxy interface.

Related tickets: DATACMNS-1324.
---
 .../data/jpa/domain/AbstractPersistable.java  |  4 +-
 .../data/jpa/util/HibernateProxyDetector.java | 54 +++++++++++++++++++
 src/main/resources/META-INF/spring.factories  |  1 +
 3 files changed, 57 insertions(+), 2 deletions(-)
 create mode 100644 src/main/java/org/springframework/data/jpa/util/HibernateProxyDetector.java

diff --git a/src/main/java/org/springframework/data/jpa/domain/AbstractPersistable.java b/src/main/java/org/springframework/data/jpa/domain/AbstractPersistable.java
index 47e1736d5..3a51f2e7c 100644
--- a/src/main/java/org/springframework/data/jpa/domain/AbstractPersistable.java
+++ b/src/main/java/org/springframework/data/jpa/domain/AbstractPersistable.java
@@ -23,8 +23,8 @@ import javax.persistence.MappedSuperclass;
 import javax.persistence.Transient;
 
 import org.springframework.data.domain.Persistable;
+import org.springframework.data.util.ProxyUtils;
 import org.springframework.lang.Nullable;
-import org.springframework.util.ClassUtils;
 
 /**
  * Abstract base class for entities. Allows parameterization of id type, chooses auto-generation and implements
@@ -94,7 +94,7 @@ public abstract class AbstractPersistable<PK extends Serializable> implements Pe
 			return true;
 		}
 
-		if (!getClass().equals(ClassUtils.getUserClass(obj))) {
+		if (!getClass().equals(ProxyUtils.getUserClass(obj))) {
 			return false;
 		}
 
diff --git a/src/main/java/org/springframework/data/jpa/util/HibernateProxyDetector.java b/src/main/java/org/springframework/data/jpa/util/HibernateProxyDetector.java
new file mode 100644
index 000000000..e48393426
--- /dev/null
+++ b/src/main/java/org/springframework/data/jpa/util/HibernateProxyDetector.java
@@ -0,0 +1,54 @@
+/*
+ * Copyright 2018 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.jpa.util;
+
+import java.util.Optional;
+
+import org.hibernate.proxy.HibernateProxy;
+import org.springframework.data.util.ProxyUtils.ProxyDetector;
+import org.springframework.util.ClassUtils;
+
+/**
+ * {@link org.springframework.data.util.ProxyDetector} to explicitly check for Hibernate's {@link HibernateProxy}.
+ * 
+ * @author Oliver Gierke
+ */
+class HibernateProxyDetector implements ProxyDetector {
+
+	private static final Optional<Class<?>> HIBERNATE_PROXY = Optional.ofNullable(loadHibernateProxyType());
+
+	/* 
+	 * (non-Javadoc)
+	 * @see org.springframework.data.util.ProxyUtils.ProxyDetector#getUserType(java.lang.Class)
+	 */
+	@Override
+	public Class<?> getUserType(Class<?> type) {
+
+		return HIBERNATE_PROXY //
+				.map(it -> it.isAssignableFrom(type) ? type.getSuperclass() : type) //
+				.filter(it -> !Object.class.equals(it)) //
+				.orElse(type);
+	}
+
+	private static final Class<?> loadHibernateProxyType() {
+
+		try {
+			return ClassUtils.forName("org.hibernate.proxy.HibernateProxy", HibernateProxyDetector.class.getClassLoader());
+		} catch (ClassNotFoundException o_O) {
+			return null;
+		}
+	}
+}
diff --git a/src/main/resources/META-INF/spring.factories b/src/main/resources/META-INF/spring.factories
index 2418f4a36..cf6372d62 100644
--- a/src/main/resources/META-INF/spring.factories
+++ b/src/main/resources/META-INF/spring.factories
@@ -1 +1,2 @@
 org.springframework.data.repository.core.support.RepositoryFactorySupport=org.springframework.data.jpa.repository.support.JpaRepositoryFactory
+org.springframework.data.util.ProxyUtils$ProxyDetector=org.springframework.data.jpa.util.HibernateProxyDetector