Fix lazy loading problem with custom revision entities.

We now unproxy the revision data before trying to access its data.

Closes #313

Author: schauder

src/main/java/org/springframework/data/envers/repository/support/EnversRevisionRepositoryImpl.java

@@ -23,6 +23,7 @@
 
 import javax.persistence.EntityManager;
 
+import org.hibernate.Hibernate;
 import org.hibernate.envers.AuditReader;
 import org.hibernate.envers.AuditReaderFactory;
 import org.hibernate.envers.DefaultRevisionEntity;
@@ -32,7 +33,6 @@
 import org.hibernate.envers.query.AuditEntity;
 import org.hibernate.envers.query.AuditQuery;
 import org.hibernate.envers.query.order.AuditOrder;
-
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.PageImpl;
 import org.springframework.data.domain.Pageable;
@@ -208,7 +208,8 @@ RevisionMetadata<?> createRevisionMetadata() {
 
 			return metadata instanceof DefaultRevisionEntity //
 					? new DefaultRevisionMetadata((DefaultRevisionEntity) metadata, revisionType) //
-					: new AnnotationRevisionMetadata<>(metadata, RevisionNumber.class, RevisionTimestamp.class, revisionType);
+					: new AnnotationRevisionMetadata<>(Hibernate.unproxy(metadata), RevisionNumber.class, RevisionTimestamp.class,
+							revisionType);
 		}
 
 		private static RevisionMetadata.RevisionType convertRevisionType(RevisionType datum) {

src/test/java/org/springframework/data/envers/repository/support/RepositoryIntegrationTests.java

@@ -106,7 +106,10 @@ void testLifeCycle() {
 
 			Page<Revision<Integer, License>> page = licenseRepository.findRevisions(license.id, PageRequest.of(0, 10));
 			Revisions<Integer, License> revisions = Revisions.of(page.getContent());
-			assertThat(revisions.getLatestRevision()).isEqualTo(it);
+			Revision<Integer, License> latestRevision = revisions.getLatestRevision();
+
+			assertThat(latestRevision.getRequiredRevisionNumber()).isEqualTo(it.getRequiredRevisionNumber());
+			assertThat(latestRevision.getEntity()).isEqualTo(it.getEntity());
 		});
 	}
 

src/test/java/org/springframework/data/envers/sample/CustomRevisionEntity.java

@@ -0,0 +1,69 @@
+/*
+ * Copyright 2021 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
+ *
+ *      https://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.envers.sample;
+
+import org.hibernate.envers.DefaultRevisionEntity;
+import org.hibernate.envers.RevisionEntity;
+import org.hibernate.envers.RevisionNumber;
+import org.hibernate.envers.RevisionTimestamp;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.Transient;
+import java.util.Date;
+
+@Entity
+@RevisionEntity(CustomRevisionListener.class)
+public class CustomRevisionEntity  {
+
+	@Id
+	@GeneratedValue
+	@RevisionNumber
+	private int id;
+	@RevisionTimestamp
+	private long timestamp;
+	private String additionalData;
+
+	public int getId() {
+		return this.id;
+	}
+
+	public void setId(int id) {
+		this.id = id;
+	}
+
+	@Transient
+	public Date getRevisionDate() {
+		return new Date(this.timestamp);
+	}
+
+	public long getTimestamp() {
+		return this.timestamp;
+	}
+
+	public void setTimestamp(long timestamp) {
+		this.timestamp = timestamp;
+	}
+	public String getAdditionalData() {
+		return additionalData;
+	}
+
+	public void setAdditionalData(String additionalData) {
+		this.additionalData = additionalData;
+	}
+
+}

src/test/java/org/springframework/data/envers/sample/CustomRevisionListener.java

@@ -0,0 +1,25 @@
+/*
+ * Copyright 2021 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
+ *
+ *      https://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.envers.sample;
+
+import org.hibernate.envers.RevisionListener;
+
+public class CustomRevisionListener implements RevisionListener {
+	@Override
+	public void newRevision(Object o) {
+		((CustomRevisionEntity) o).setAdditionalData("some data");
+	}
+}