HHH-8174 - Envers support for @NotFound

documentation/src/main/docbook/devguide/en-US/Envers.xml

@@ -380,8 +380,12 @@
         <para>
             If you want to audit a relation, where the target entity is not audited (that is the case for example with
             dictionary-like entities, which don't change and don't have to be audited), just annotate it with
-            <literal>@Audited(targetAuditMode = RelationTargetAuditMode.NOT_AUDITED)</literal>. Then, when reading historic
+            <literal>@Audited(targetAuditMode = RelationTargetAuditMode.NOT_AUDITED)</literal>. Then, while reading historic
-            versions of your entity, the relation will always point to the "current" related entity.
+            versions of your entity, the relation will always point to the "current" related entity. By default Envers
+            throws <classname>javax.persistence.EntityNotFoundException</classname> when "current" entity does not
+            exist in the database. Apply <literal>@NotFound(action = NotFoundAction.IGNORE)</literal> annotation
+            to silence the exception and assign null value instead. Hereby solution causes implicit eager loading
+            of to-one relations.
         </para>
 
         <para>

hibernate-envers/src/main/java/org/hibernate/envers/configuration/internal/metadata/ToOneRelationMetadataGenerator.java

@@ -77,10 +77,8 @@ public final class ToOneRelationMetadataGenerator {
 
 		// Storing information about this relation
 		mainGenerator.getEntitiesConfigurations().get( entityName ).addToOneRelation(
-				propertyAuditingData.getName(),
+				propertyAuditingData.getName(), referencedEntityName, relMapper,
-				referencedEntityName,
+				insertable, MappingTools.ignoreNotFound( value )
-				relMapper,
-				insertable
 		);
 
 		// If the property isn't insertable, checking if this is not a "fake" bidirectional many-to-one relationship,
@@ -154,10 +152,8 @@ public final class ToOneRelationMetadataGenerator {
 
 		// Storing information about this relation
 		mainGenerator.getEntitiesConfigurations().get( entityName ).addToOneNotOwningRelation(
-				propertyAuditingData.getName(),
+				propertyAuditingData.getName(), owningReferencePropertyName, referencedEntityName,
-				owningReferencePropertyName,
+				ownedIdMapper, MappingTools.ignoreNotFound( value )
-				referencedEntityName,
-				ownedIdMapper
 		);
 
 		// Adding mapper for the id
@@ -191,10 +187,8 @@ public final class ToOneRelationMetadataGenerator {
 
 		// Storing information about this relation
 		mainGenerator.getEntitiesConfigurations().get( entityName ).addToOneRelation(
-				propertyAuditingData.getName(),
+				propertyAuditingData.getName(), referencedEntityName, relMapper, insertable,
-				referencedEntityName,
+				MappingTools.ignoreNotFound( value )
-				relMapper,
-				insertable
 		);
 
 		// Adding mapper for the id

hibernate-envers/src/main/java/org/hibernate/envers/internal/entities/EntityConfiguration.java

@@ -46,8 +46,7 @@ public class EntityConfiguration {
 	private Map<String, RelationDescription> relations;
 	private String parentEntityName;
 
-	public EntityConfiguration(
+	public EntityConfiguration(String versionsEntityName, String entityClassName, IdMappingData idMappingData,
-			String versionsEntityName, String entityClassName, IdMappingData idMappingData,
 							   ExtendedPropertyMapper propertyMapper, String parentEntityName) {
 		this.versionsEntityName = versionsEntityName;
 		this.entityClassName = entityClassName;
@@ -58,60 +57,36 @@ public class EntityConfiguration {
 		this.relations = new HashMap<String, RelationDescription>();
 	}
 
-	public void addToOneRelation(String fromPropertyName, String toEntityName, IdMapper idMapper, boolean insertable) {
+	public void addToOneRelation(String fromPropertyName, String toEntityName, IdMapper idMapper, boolean insertable,
+								 boolean ignoreNotFound) {
 		relations.put(
 				fromPropertyName,
-				new RelationDescription(
+				RelationDescription.toOne(
-						fromPropertyName,
+						fromPropertyName, RelationType.TO_ONE, toEntityName, null, idMapper, null,
-						RelationType.TO_ONE,
+						null, insertable, ignoreNotFound
-						toEntityName,
-						null,
-						idMapper,
-						null,
-						null,
-						insertable
 				)
 		);
 	}
 
-	public void addToOneNotOwningRelation(
+	public void addToOneNotOwningRelation(String fromPropertyName, String mappedByPropertyName,
-			String fromPropertyName,
+										  String toEntityName, IdMapper idMapper, boolean ignoreNotFound) {
-			String mappedByPropertyName,
-			String toEntityName,
-			IdMapper idMapper) {
 		relations.put(
 				fromPropertyName,
-				new RelationDescription(
+				RelationDescription.toOne(
-						fromPropertyName,
+						fromPropertyName, RelationType.TO_ONE_NOT_OWNING, toEntityName, mappedByPropertyName,
-						RelationType.TO_ONE_NOT_OWNING,
+						idMapper, null, null, true, ignoreNotFound
-						toEntityName,
-						mappedByPropertyName,
-						idMapper,
-						null,
-						null,
-						true
 				)
 		);
 	}
 
-	public void addToManyNotOwningRelation(
+	public void addToManyNotOwningRelation(String fromPropertyName, String mappedByPropertyName, String toEntityName,
-			String fromPropertyName,
+										   IdMapper idMapper, PropertyMapper fakeBidirectionalRelationMapper,
-			String mappedByPropertyName,
-			String toEntityName,
-			IdMapper idMapper,
-			PropertyMapper fakeBidirectionalRelationMapper,
 										   PropertyMapper fakeBidirectionalRelationIndexMapper) {
 		relations.put(
 				fromPropertyName,
-				new RelationDescription(
+				RelationDescription.toMany(
-						fromPropertyName,
+						fromPropertyName, RelationType.TO_MANY_NOT_OWNING, toEntityName, mappedByPropertyName,
-						RelationType.TO_MANY_NOT_OWNING,
+						idMapper, fakeBidirectionalRelationMapper, fakeBidirectionalRelationIndexMapper, true
-						toEntityName,
-						mappedByPropertyName,
-						idMapper,
-						fakeBidirectionalRelationMapper,
-						fakeBidirectionalRelationIndexMapper,
-						true
 				)
 		);
 	}
@@ -119,34 +94,18 @@ public class EntityConfiguration {
 	public void addToManyMiddleRelation(String fromPropertyName, String toEntityName) {
 		relations.put(
 				fromPropertyName,
-				new RelationDescription(
+				RelationDescription.toMany(
-						fromPropertyName,
+						fromPropertyName, RelationType.TO_MANY_MIDDLE, toEntityName, null, null, null, null, true
-						RelationType.TO_MANY_MIDDLE,
-						toEntityName,
-						null,
-						null,
-						null,
-						null,
-						true
 				)
 		);
 	}
 
-	public void addToManyMiddleNotOwningRelation(
+	public void addToManyMiddleNotOwningRelation(String fromPropertyName, String mappedByPropertyName, String toEntityName) {
-			String fromPropertyName,
-			String mappedByPropertyName,
-			String toEntityName) {
 		relations.put(
 				fromPropertyName,
-				new RelationDescription(
+				RelationDescription.toMany(
-						fromPropertyName,
+						fromPropertyName, RelationType.TO_MANY_MIDDLE_NOT_OWNING, toEntityName, mappedByPropertyName,
-						RelationType.TO_MANY_MIDDLE_NOT_OWNING,
+						null, null, null, true
-						toEntityName,
-						mappedByPropertyName,
-						null,
-						null,
-						null,
-						true
 				)
 		);
 	}
@@ -175,6 +134,13 @@ public class EntityConfiguration {
 		return parentEntityName;
 	}
 
+	/**
+	 * @return the className for the configured entity
+	 */
+	public String getEntityClassName() {
+		return entityClassName;
+	}
+
 	// For use by EntitiesConfigurations
 
 	String getVersionsEntityName() {
@@ -184,11 +150,4 @@ public class EntityConfiguration {
 	Iterable<RelationDescription> getRelationsIterator() {
 		return relations.values();
 	}
-
-	/**
-	 * @return the className for the configured entity
-	 */
-	public String getEntityClassName() {
-		return entityClassName;
-	}
 }

hibernate-envers/src/main/java/org/hibernate/envers/internal/entities/RelationDescription.java

@@ -34,21 +34,44 @@ public class RelationDescription {
 	private final RelationType relationType;
 	private final String toEntityName;
 	private final String mappedByPropertyName;
+	private final boolean ignoreNotFound;
 	private final IdMapper idMapper;
 	private final PropertyMapper fakeBidirectionalRelationMapper;
 	private final PropertyMapper fakeBidirectionalRelationIndexMapper;
 	private final boolean insertable;
 	private boolean bidirectional;
 
-	public RelationDescription(
+	public static RelationDescription toOne(String fromPropertyName, RelationType relationType, String toEntityName,
-			String fromPropertyName, RelationType relationType, String toEntityName,
+											String mappedByPropertyName, IdMapper idMapper, PropertyMapper fakeBidirectionalRelationMapper,
-			String mappedByPropertyName, IdMapper idMapper,
+											PropertyMapper fakeBidirectionalRelationIndexMapper, boolean insertable,
-			PropertyMapper fakeBidirectionalRelationMapper,
+											boolean ignoreNotFound) {
+		return new RelationDescription(
+				fromPropertyName, relationType, toEntityName, mappedByPropertyName, idMapper, fakeBidirectionalRelationMapper,
+				fakeBidirectionalRelationIndexMapper, insertable, ignoreNotFound
+		);
+	}
+
+	public static RelationDescription toMany(String fromPropertyName, RelationType relationType, String toEntityName,
+											 String mappedByPropertyName, IdMapper idMapper, PropertyMapper fakeBidirectionalRelationMapper,
 											 PropertyMapper fakeBidirectionalRelationIndexMapper, boolean insertable) {
+		// Envers populates collections by executing dedicated queries. Special handling of
+		// @NotFound(action = NotFoundAction.IGNORE) can be omitted in such case as exceptions
+		// (e.g. EntityNotFoundException, ObjectNotFoundException) are never thrown.
+		// Therefore assigning false to ignoreNotFound.
+		return new RelationDescription(
+				fromPropertyName, relationType, toEntityName, mappedByPropertyName, idMapper, fakeBidirectionalRelationMapper,
+				fakeBidirectionalRelationIndexMapper, insertable, false
+		);
+	}
+
+	private RelationDescription(String fromPropertyName, RelationType relationType, String toEntityName,
+								String mappedByPropertyName, IdMapper idMapper, PropertyMapper fakeBidirectionalRelationMapper,
+								PropertyMapper fakeBidirectionalRelationIndexMapper, boolean insertable, boolean ignoreNotFound) {
 		this.fromPropertyName = fromPropertyName;
 		this.relationType = relationType;
 		this.toEntityName = toEntityName;
 		this.mappedByPropertyName = mappedByPropertyName;
+		this.ignoreNotFound = ignoreNotFound;
 		this.idMapper = idMapper;
 		this.fakeBidirectionalRelationMapper = fakeBidirectionalRelationMapper;
 		this.fakeBidirectionalRelationIndexMapper = fakeBidirectionalRelationIndexMapper;
@@ -73,6 +96,10 @@ public class RelationDescription {
 		return mappedByPropertyName;
 	}
 
+	public boolean isIgnoreNotFound() {
+		return ignoreNotFound;
+	}
+
 	public IdMapper getIdMapper() {
 		return idMapper;
 	}

hibernate-envers/src/main/java/org/hibernate/envers/internal/entities/mapper/relation/ToOneEntityLoader.java

@@ -35,7 +35,8 @@ import org.hibernate.persister.entity.EntityPersister;
  */
 public class ToOneEntityLoader {
 	/**
-	 * Immediately loads historical entity or its current state when excluded from audit process.
+	 * Immediately loads historical entity or its current state when excluded from audit process. Returns {@code null}
+	 * reference if entity has not been found in the database.
 	 */
 	public static Object loadImmediate(
 			AuditReaderImplementor versionsReader,

hibernate-envers/src/main/java/org/hibernate/envers/internal/entities/mapper/relation/ToOneIdMapper.java

@@ -45,10 +45,7 @@ public class ToOneIdMapper extends AbstractToOneMapper {
 	private final String referencedEntityName;
 	private final boolean nonInsertableFake;
 
-	public ToOneIdMapper(
+	public ToOneIdMapper(IdMapper delegate, PropertyData propertyData, String referencedEntityName,
-			IdMapper delegate,
-			PropertyData propertyData,
-			String referencedEntityName,
 						 boolean nonInsertableFake) {
 		super( propertyData );
 		this.delegate = delegate;
@@ -57,10 +54,7 @@ public class ToOneIdMapper extends AbstractToOneMapper {
 	}
 
 	@Override
-	public boolean mapToMapFromEntity(
+	public boolean mapToMapFromEntity(SessionImplementor session, Map<String, Object> data, Object newObj,
-			SessionImplementor session,
-			Map<String, Object> data,
-			Object newObj,
 									  Object oldObj) {
 		final HashMap<String, Object> newData = new HashMap<String, Object>();
 
@@ -77,10 +71,7 @@ public class ToOneIdMapper extends AbstractToOneMapper {
 	}
 
 	@Override
-	public void mapModifiedFlagsToMapFromEntity(
+	public void mapModifiedFlagsToMapFromEntity(SessionImplementor session, Map<String, Object> data, Object newObj,
-			SessionImplementor session,
-			Map<String, Object> data,
-			Object newObj,
 												Object oldObj) {
 		if ( getPropertyData().isUsingModifiedFlag() ) {
 			data.put( getPropertyData().getModifiedFlagPropertyName(), checkModified( session, newObj, oldObj ) );
@@ -103,8 +94,7 @@ public class ToOneIdMapper extends AbstractToOneMapper {
 	}
 
 	@Override
-	public void nullSafeMapToEntityFromMap(
+	public void nullSafeMapToEntityFromMap(AuditConfiguration verCfg, Object obj, Map data, Object primaryKey,
-			AuditConfiguration verCfg, Object obj, Map data, Object primaryKey,
 										   AuditReaderImplementor versionsReader, Number revision) {
 		final Object entityId = delegate.mapToIdFromMap( data );
 		Object value = null;
@@ -114,27 +104,35 @@ public class ToOneIdMapper extends AbstractToOneMapper {
 			}
 			else {
 				final EntityInfo referencedEntity = getEntityInfo( verCfg, referencedEntityName );
+				boolean ignoreNotFound = false;
+				if ( !referencedEntity.isAudited() ) {
+					final String referencingEntityName = verCfg.getEntCfg().getEntityNameForVersionsEntityName( (String) data.get( "$type$" ) );
+					ignoreNotFound = verCfg.getEntCfg().get( referencingEntityName ).getRelationDescription( getPropertyData().getName() ).isIgnoreNotFound();
+				}
+				if ( ignoreNotFound ) {
+					// Eagerly loading referenced entity to silence potential (in case of proxy)
+					// EntityNotFoundException or ObjectNotFoundException. Assigning null reference.
+					value = ToOneEntityLoader.loadImmediate(
+							versionsReader, referencedEntity.getEntityClass(), referencedEntityName,
+							entityId, revision, RevisionType.DEL.equals( data.get( verCfg.getAuditEntCfg().getRevisionTypePropName() ) ),
+							verCfg
+					);
+				}
+				else {
 					value = ToOneEntityLoader.createProxyOrLoadImmediate(
 							versionsReader, referencedEntity.getEntityClass(), referencedEntityName,
-						entityId, revision, RevisionType.DEL.equals(
+							entityId, revision, RevisionType.DEL.equals( data.get( verCfg.getAuditEntCfg().getRevisionTypePropName() ) ),
-						data.get(
+							verCfg
-								verCfg.getAuditEntCfg()
-										.getRevisionTypePropName()
-						)
-				), verCfg
 					);
 				}
 			}
+		}
 
 		setPropertyValue( obj, value );
 	}
 
-	public void addMiddleEqualToQuery(
+	public void addMiddleEqualToQuery(Parameters parameters, String idPrefix1, String prefix1,
-			Parameters parameters,
+									  String idPrefix2, String prefix2) {
-			String idPrefix1,
-			String prefix1,
-			String idPrefix2,
-			String prefix2) {
 		delegate.addIdsEqualToQuery( parameters, prefix1, delegate, prefix2 );
 	}
 }

hibernate-envers/src/main/java/org/hibernate/envers/internal/tools/MappingTools.java

@@ -24,6 +24,7 @@
 package org.hibernate.envers.internal.tools;
 
 import org.hibernate.mapping.Collection;
+import org.hibernate.mapping.ManyToOne;
 import org.hibernate.mapping.OneToMany;
 import org.hibernate.mapping.ToOne;
 import org.hibernate.mapping.Value;
@@ -63,4 +64,18 @@ public abstract class MappingTools {
 
 		return null;
 	}
+
+	/**
+	 * @param value Persistent property.
+	 * @return {@code false} if lack of associated entity shall raise an exception, {@code true} otherwise.
+	 */
+	public static boolean ignoreNotFound(Value value) {
+		if ( value instanceof ManyToOne ) {
+			return ( (ManyToOne) value ).isIgnoreNotFound();
+		}
+		else if ( value instanceof OneToMany ) {
+			return ( (OneToMany) value ).isIgnoreNotFound();
+		}
+		return false;
+	}
 }

hibernate-envers/src/test/java/org/hibernate/envers/test/entities/manytomany/unidirectional/ManyToManyNotAuditedNullEntity.java

@@ -0,0 +1,111 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2008, 2013, Red Hat Inc. or third-party contributors as
+ * indicated by the @author tags or express copyright attribution
+ * statements applied by the authors.  All third-party contributions are
+ * distributed under license by Red Hat Inc.
+ *
+ * This copyrighted material is made available to anyone wishing to use, modify,
+ * copy, or redistribute it subject to the terms and conditions of the GNU
+ * Lesser General Public License, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this distribution; if not, write to:
+ * Free Software Foundation, Inc.
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA  02110-1301  USA
+ */
+package org.hibernate.envers.test.entities.manytomany.unidirectional;
+
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.List;
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.Id;
+import javax.persistence.ManyToMany;
+import javax.persistence.Table;
+
+import org.hibernate.annotations.NotFound;
+import org.hibernate.annotations.NotFoundAction;
+import org.hibernate.envers.Audited;
+import org.hibernate.envers.RelationTargetAuditMode;
+import org.hibernate.envers.test.entities.UnversionedStrTestEntity;
+
+/**
+ * @author Lukasz Antoniak (lukasz dot antoniak at gmail dot com)
+ */
+@Audited
+@Entity
+@Table(name = "M2M_N_AUD_NULL")
+public class ManyToManyNotAuditedNullEntity implements Serializable {
+	@Id
+	private Integer id;
+
+	private String data;
+
+	@Audited(targetAuditMode = RelationTargetAuditMode.NOT_AUDITED)
+	@ManyToMany(fetch = FetchType.LAZY)
+	@NotFound(action = NotFoundAction.IGNORE)
+	private List<UnversionedStrTestEntity> references = new ArrayList<UnversionedStrTestEntity>();
+
+	protected ManyToManyNotAuditedNullEntity() {
+	}
+
+	public ManyToManyNotAuditedNullEntity(Integer id, String data) {
+		this.id = id;
+		this.data = data;
+	}
+
+	public boolean equals(Object o) {
+		if ( this == o ) return true;
+		if ( !( o instanceof ManyToManyNotAuditedNullEntity ) ) return false;
+
+		ManyToManyNotAuditedNullEntity that = (ManyToManyNotAuditedNullEntity) o;
+
+		if ( data != null ? !data.equals( that.getData() ) : that.getData() != null ) return false;
+		if ( id != null ? !id.equals( that.getId() ) : that.getId() != null ) return false;
+
+		return true;
+	}
+
+	public int hashCode() {
+		int result = ( id != null ? id.hashCode() : 0 );
+		result = 31 * result + ( data != null ? data.hashCode() : 0 );
+		return result;
+	}
+
+	public String toString() {
+		return "ManyToManyNotAuditedNullEntity(id = " + id + ", data = " + data + ")";
+	}
+
+	public Integer getId() {
+		return id;
+	}
+
+	public void setId(Integer id) {
+		this.id = id;
+	}
+
+	public String getData() {
+		return data;
+	}
+
+	public void setData(String data) {
+		this.data = data;
+	}
+
+	public List<UnversionedStrTestEntity> getReferences() {
+		return references;
+	}
+
+	public void setReferences(List<UnversionedStrTestEntity> references) {
+		this.references = references;
+	}
+}

hibernate-envers/src/test/java/org/hibernate/envers/test/entities/manytoone/unidirectional/ManyToOneNotAuditedNullEntity.java

@@ -0,0 +1,110 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2008, 2013, Red Hat Inc. or third-party contributors as
+ * indicated by the @author tags or express copyright attribution
+ * statements applied by the authors.  All third-party contributions are
+ * distributed under license by Red Hat Inc.
+ *
+ * This copyrighted material is made available to anyone wishing to use, modify,
+ * copy, or redistribute it subject to the terms and conditions of the GNU
+ * Lesser General Public License, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this distribution; if not, write to:
+ * Free Software Foundation, Inc.
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA  02110-1301  USA
+ */
+package org.hibernate.envers.test.entities.manytoone.unidirectional;
+
+import java.io.Serializable;
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.Id;
+import javax.persistence.ManyToOne;
+import javax.persistence.Table;
+
+import org.hibernate.annotations.NotFound;
+import org.hibernate.annotations.NotFoundAction;
+import org.hibernate.envers.Audited;
+import org.hibernate.envers.RelationTargetAuditMode;
+import org.hibernate.envers.test.entities.UnversionedStrTestEntity;
+
+/**
+ * @author Lukasz Antoniak (lukasz dot antoniak at gmail dot com)
+ */
+@Audited
+@Entity
+@Table(name = "M2O_N_AUD_NULL")
+public class ManyToOneNotAuditedNullEntity implements Serializable {
+	@Id
+	private Integer id;
+
+	private String data;
+
+	@Audited(targetAuditMode = RelationTargetAuditMode.NOT_AUDITED)
+	@ManyToOne(fetch = FetchType.LAZY, optional = true)
+	@NotFound(action = NotFoundAction.IGNORE)
+	private UnversionedStrTestEntity reference;
+
+	protected ManyToOneNotAuditedNullEntity() {
+	}
+
+	public ManyToOneNotAuditedNullEntity(Integer id, String data, UnversionedStrTestEntity reference) {
+		this.id = id;
+		this.data = data;
+		this.reference = reference;
+	}
+
+	public boolean equals(Object o) {
+		if ( this == o ) return true;
+		if ( !( o instanceof ManyToOneNotAuditedNullEntity ) ) return false;
+
+		ManyToOneNotAuditedNullEntity that = (ManyToOneNotAuditedNullEntity) o;
+
+		if ( data != null ? !data.equals( that.getData() ) : that.getData() != null ) return false;
+		if ( id != null ? !id.equals( that.getId() ) : that.getId() != null ) return false;
+
+		return true;
+	}
+
+	public int hashCode() {
+		int result = ( id != null ? id.hashCode() : 0 );
+		result = 31 * result + ( data != null ? data.hashCode() : 0 );
+		return result;
+	}
+
+	public String toString() {
+		return "ManyToOneNotAuditedNullEntity(id = " + id + ", data = " + data + ")";
+	}
+
+	public Integer getId() {
+		return id;
+	}
+
+	public void setId(Integer id) {
+		this.id = id;
+	}
+
+	public String getData() {
+		return data;
+	}
+
+	public void setData(String data) {
+		this.data = data;
+	}
+
+	public UnversionedStrTestEntity getReference() {
+		return reference;
+	}
+
+	public void setReference(UnversionedStrTestEntity reference) {
+		this.reference = reference;
+	}
+}

hibernate-envers/src/test/java/org/hibernate/envers/test/entities/onetomany/OneToManyNotAuditedNullEntity.java

@@ -0,0 +1,111 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2008, 2013, Red Hat Inc. or third-party contributors as
+ * indicated by the @author tags or express copyright attribution
+ * statements applied by the authors.  All third-party contributions are
+ * distributed under license by Red Hat Inc.
+ *
+ * This copyrighted material is made available to anyone wishing to use, modify,
+ * copy, or redistribute it subject to the terms and conditions of the GNU
+ * Lesser General Public License, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this distribution; if not, write to:
+ * Free Software Foundation, Inc.
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA  02110-1301  USA
+ */
+package org.hibernate.envers.test.entities.onetomany;
+
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.List;
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.Id;
+import javax.persistence.OneToMany;
+import javax.persistence.Table;
+
+import org.hibernate.annotations.NotFound;
+import org.hibernate.annotations.NotFoundAction;
+import org.hibernate.envers.Audited;
+import org.hibernate.envers.RelationTargetAuditMode;
+import org.hibernate.envers.test.entities.UnversionedStrTestEntity;
+
+/**
+ * @author Lukasz Antoniak (lukasz dot antoniak at gmail dot com)
+ */
+@Audited
+@Entity
+@Table(name = "O2M_N_AUD_NULL")
+public class OneToManyNotAuditedNullEntity implements Serializable {
+	@Id
+	private Integer id;
+
+	private String data;
+
+	@Audited(targetAuditMode = RelationTargetAuditMode.NOT_AUDITED)
+	@OneToMany(fetch = FetchType.LAZY)
+	@NotFound(action = NotFoundAction.IGNORE)
+	private List<UnversionedStrTestEntity> references = new ArrayList<UnversionedStrTestEntity>();
+
+	protected OneToManyNotAuditedNullEntity() {
+	}
+
+	public OneToManyNotAuditedNullEntity(Integer id, String data) {
+		this.id = id;
+		this.data = data;
+	}
+
+	public boolean equals(Object o) {
+		if ( this == o ) return true;
+		if ( !( o instanceof OneToManyNotAuditedNullEntity ) ) return false;
+
+		OneToManyNotAuditedNullEntity that = (OneToManyNotAuditedNullEntity) o;
+
+		if ( data != null ? !data.equals( that.getData() ) : that.getData() != null ) return false;
+		if ( id != null ? !id.equals( that.getId() ) : that.getId() != null ) return false;
+
+		return true;
+	}
+
+	public int hashCode() {
+		int result = ( id != null ? id.hashCode() : 0 );
+		result = 31 * result + ( data != null ? data.hashCode() : 0 );
+		return result;
+	}
+
+	public String toString() {
+		return "OneToManyNotAuditedNullEntity(id = " + id + ", data = " + data + ")";
+	}
+
+	public Integer getId() {
+		return id;
+	}
+
+	public void setId(Integer id) {
+		this.id = id;
+	}
+
+	public String getData() {
+		return data;
+	}
+
+	public void setData(String data) {
+		this.data = data;
+	}
+
+	public List<UnversionedStrTestEntity> getReferences() {
+		return references;
+	}
+
+	public void setReferences(List<UnversionedStrTestEntity> references) {
+		this.references = references;
+	}
+}

hibernate-envers/src/test/java/org/hibernate/envers/test/integration/proxy/ProxyIdentifier.java

@@ -25,26 +25,37 @@ package org.hibernate.envers.test.integration.proxy;
 
 import javax.persistence.EntityManager;
 
+import org.junit.Assert;
+import org.junit.Test;
+
 import org.hibernate.envers.test.BaseEnversJPAFunctionalTestCase;
 import org.hibernate.envers.test.Priority;
 import org.hibernate.envers.test.entities.UnversionedStrTestEntity;
+import org.hibernate.envers.test.entities.manytomany.unidirectional.ManyToManyNotAuditedNullEntity;
+import org.hibernate.envers.test.entities.manytoone.unidirectional.ManyToOneNotAuditedNullEntity;
 import org.hibernate.envers.test.entities.manytoone.unidirectional.TargetNotAuditedEntity;
+import org.hibernate.envers.test.entities.onetomany.OneToManyNotAuditedNullEntity;
 import org.hibernate.proxy.HibernateProxy;
 import org.hibernate.proxy.LazyInitializer;
-
+import org.hibernate.testing.TestForIssue;
-import org.junit.Test;
-
 
 /**
  * @author Eugene Goroschenya
  */
 public class ProxyIdentifier extends BaseEnversJPAFunctionalTestCase {
-	private TargetNotAuditedEntity tnae1;
+	private TargetNotAuditedEntity tnae1 = null;
-	private UnversionedStrTestEntity uste1;
+	private ManyToOneNotAuditedNullEntity mtonane1 = null;
+	private ManyToManyNotAuditedNullEntity mtmnane1 = null;
+	private OneToManyNotAuditedNullEntity otmnane1 = null;
+	private UnversionedStrTestEntity uste1 = null;
+	private UnversionedStrTestEntity uste2 = null;
 
 	@Override
 	protected Class<?>[] getAnnotatedClasses() {
-		return new Class[] {TargetNotAuditedEntity.class, UnversionedStrTestEntity.class};
+		return new Class[] {
+				TargetNotAuditedEntity.class, ManyToOneNotAuditedNullEntity.class, UnversionedStrTestEntity.class,
+				ManyToManyNotAuditedNullEntity.class, OneToManyNotAuditedNullEntity.class
+		};
 	}
 
 	@Test
@@ -53,10 +64,12 @@ public class ProxyIdentifier extends BaseEnversJPAFunctionalTestCase {
 		EntityManager em = getEntityManager();
 
 		uste1 = new UnversionedStrTestEntity( "str1" );
+		uste2 = new UnversionedStrTestEntity( "str2" );
 
 		// No revision
 		em.getTransaction().begin();
 		em.persist( uste1 );
+		em.persist( uste2 );
 		em.getTransaction().commit();
 
 		// Revision 1
@@ -65,24 +78,73 @@ public class ProxyIdentifier extends BaseEnversJPAFunctionalTestCase {
 		tnae1 = new TargetNotAuditedEntity( 1, "tnae1", uste1 );
 		em.persist( tnae1 );
 		em.getTransaction().commit();
+
+		// Revision 2
+		em.getTransaction().begin();
+		uste2 = em.find( UnversionedStrTestEntity.class, uste2.getId() );
+		mtonane1 = new ManyToOneNotAuditedNullEntity( 2, "mtonane1", uste2 );
+		mtmnane1 = new ManyToManyNotAuditedNullEntity( 3, "mtmnane1" );
+		mtmnane1.getReferences().add( uste2 );
+		otmnane1 = new OneToManyNotAuditedNullEntity( 4, "otmnane1" );
+		otmnane1.getReferences().add( uste2 );
+		em.persist( mtonane1 );
+		em.persist( mtmnane1 );
+		em.persist( otmnane1 );
+		em.getTransaction().commit();
+
+		em.clear();
+
+		// Revision 3
+		// Remove not audited target entity, so we can verify null reference
+		// when @NotFound(action = NotFoundAction.IGNORE) applied.
+		em.getTransaction().begin();
+		ManyToOneNotAuditedNullEntity tmp1 = em.find( ManyToOneNotAuditedNullEntity.class, mtonane1.getId() );
+		tmp1.setReference( null );
+		tmp1 = em.merge( tmp1 );
+		ManyToManyNotAuditedNullEntity tmp2 = em.find( ManyToManyNotAuditedNullEntity.class, mtmnane1.getId() );
+		tmp2.setReferences( null );
+		tmp2 = em.merge( tmp2 );
+		OneToManyNotAuditedNullEntity tmp3 = em.find( OneToManyNotAuditedNullEntity.class, otmnane1.getId() );
+		tmp3.setReferences( null );
+		tmp3 = em.merge( tmp3 );
+		em.remove( em.getReference( UnversionedStrTestEntity.class, uste2.getId() ) );
+		em.getTransaction().commit();
+
+		em.close();
 	}
 
 	@Test
 	public void testProxyIdentifier() {
 		TargetNotAuditedEntity rev1 = getAuditReader().find( TargetNotAuditedEntity.class, tnae1.getId(), 1 );
 
-		assert rev1.getReference() instanceof HibernateProxy;
+		Assert.assertTrue( rev1.getReference() instanceof HibernateProxy );
 
 		HibernateProxy proxyCreateByEnvers = (HibernateProxy) rev1.getReference();
 		LazyInitializer lazyInitializer = proxyCreateByEnvers.getHibernateLazyInitializer();
 
-		assert lazyInitializer.isUninitialized();
+		Assert.assertTrue( lazyInitializer.isUninitialized() );
-		assert lazyInitializer.getIdentifier() != null;
+		Assert.assertNotNull( lazyInitializer.getIdentifier() );
-		assert lazyInitializer.getIdentifier().equals( tnae1.getId() );
+		Assert.assertEquals( tnae1.getId(), lazyInitializer.getIdentifier() );
-		assert lazyInitializer.isUninitialized();
+		Assert.assertTrue( lazyInitializer.isUninitialized() );
 
-		assert rev1.getReference().getId().equals( uste1.getId() );
+		Assert.assertEquals( uste1.getId(), rev1.getReference().getId() );
-		assert rev1.getReference().getStr().equals( uste1.getStr() );
+		Assert.assertEquals( uste1.getStr(), rev1.getReference().getStr() );
-		assert !lazyInitializer.isUninitialized();
+		Assert.assertFalse( lazyInitializer.isUninitialized() );
+	}
+
+	@Test
+	@TestForIssue( jiraKey = "HHH-8174" )
+	public void testNullReferenceWithNotFoundActionIgnore() {
+		ManyToOneNotAuditedNullEntity mtoRev2 = getAuditReader().find( ManyToOneNotAuditedNullEntity.class, mtonane1.getId(), 2 );
+		Assert.assertEquals( mtonane1, mtoRev2 );
+		Assert.assertNull( mtoRev2.getReference() );
+
+		ManyToManyNotAuditedNullEntity mtmRev2 = getAuditReader().find( ManyToManyNotAuditedNullEntity.class, mtmnane1.getId(), 2 );
+		Assert.assertEquals( mtmnane1, mtmRev2 );
+		Assert.assertTrue( mtmRev2.getReferences().isEmpty() );
+
+		OneToManyNotAuditedNullEntity otmRev2 = getAuditReader().find( OneToManyNotAuditedNullEntity.class, otmnane1.getId(), 2 );
+		Assert.assertEquals( otmnane1, otmRev2 );
+		Assert.assertTrue( otmRev2.getReferences().isEmpty() );
 	}
 }