AggregateMapping (Oracle Fusion Middleware Java API Reference for Oracle TopLink)

java.lang.Object
- org.eclipse.persistence.core.mappings.CoreMapping<AttributeAccessor,org.eclipse.persistence.internal.sessions.AbstractSession,org.eclipse.persistence.internal.queries.ContainerPolicy,ClassDescriptor,org.eclipse.persistence.internal.helper.DatabaseField>
- - org.eclipse.persistence.mappings.DatabaseMapping
  - - org.eclipse.persistence.mappings.AggregateMapping

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable

Direct Known Subclasses:

AbstractCompositeCollectionMapping, AbstractCompositeObjectMapping, AggregateObjectMapping, XMLInverseReferenceMapping, XMLObjectReferenceMapping
```
public abstract class AggregateMapping
extends DatabaseMapping
```
Purpose: Two objects can be considered to be related by aggregation if there is a strict 1:1 relationship between the objects. This means that if the source (parent)object exists, then the target (child or owned) object must exist. This class implements the behavior common to the aggregate object and structure mappings.

Since:

TopLink for Java 1.0

Author:

Sati

See Also:

Serialized Form

Nested Class Summary
- Nested classes/interfaces inherited from class org.eclipse.persistence.mappings.DatabaseMapping
  DatabaseMapping.WriteType

Constructor Summary

Constructors
Constructor and Description

AggregateMapping()
Default constructor.

Constructors
Constructor and Description
`AggregateMapping()` Default constructor.

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`buildBackupClone(java.lang.Object clone, java.lang.Object backup, org.eclipse.persistence.internal.sessions.UnitOfWorkImpl unitOfWork)` INTERNAL: Clone the attribute from the clone and assign it to the backup.
`void`	`buildClone(java.lang.Object original, org.eclipse.persistence.internal.identitymaps.CacheKey cacheKey, java.lang.Object clone, java.lang.Integer refreshCascade, org.eclipse.persistence.internal.sessions.AbstractSession cloningSession)` INTERNAL: Clone the attribute from the original and assign it to the clone.
`void`	`buildCloneFromRow(org.eclipse.persistence.internal.sessions.AbstractRecord databaseRow, org.eclipse.persistence.internal.queries.JoinedAttributeManager joinManager, java.lang.Object clone, org.eclipse.persistence.internal.identitymaps.CacheKey sharedCacheKey, ObjectBuildingQuery sourceQuery, org.eclipse.persistence.internal.sessions.UnitOfWorkImpl unitOfWork, org.eclipse.persistence.internal.sessions.AbstractSession executionSession)` INTERNAL: A combination of readFromRowIntoObject and buildClone.
`void`	`buildCopy(java.lang.Object copy, java.lang.Object original, CopyGroup group)` INTERNAL: Copy of the attribute of the object.
`Expression`	`buildExpression(java.lang.Object queryObject, QueryByExamplePolicy policy, Expression expressionBuilder, java.util.Map processedObjects, org.eclipse.persistence.internal.sessions.AbstractSession session)` INTERNAL: In case Query By Example is used, this method generates an expression from a attribute value pair.
`org.eclipse.persistence.internal.sessions.ChangeRecord`	`compareForChange(java.lang.Object clone, java.lang.Object backup, org.eclipse.persistence.internal.sessions.ObjectChangeSet owner, org.eclipse.persistence.internal.sessions.AbstractSession session)` INTERNAL: Compare the changes between two aggregates.
`boolean`	`compareObjects(java.lang.Object firstObject, java.lang.Object secondObject, org.eclipse.persistence.internal.sessions.AbstractSession session)` INTERNAL: Compare the attributes belonging to this mapping for the objects.
`void`	`convertClassNamesToClasses(java.lang.ClassLoader classLoader)` INTERNAL: Convert all the class-name-based settings in this mapping to actual class-based settings.
`void`	`fixObjectReferences(java.lang.Object object, java.util.Map objectDescriptors, java.util.Map processedObjects, ObjectLevelReadQuery query, DistributedSession session)` INTERNAL: An object has been serialized from the server to the remote client.
`java.lang.Class`	`getReferenceClass()` PUBLIC: Returns the reference class
`java.lang.String`	`getReferenceClassName()` INTERNAL: Used by MW.
`ClassDescriptor`	`getReferenceDescriptor()` INTERNAL: Return the referenceDescriptor.
`boolean`	`hasNestedIdentityReference()` INTERNAL: Indicates whether the mapping (or at least one of its nested mappings, at any nested depth) references an entity.
`void`	`initialize(org.eclipse.persistence.internal.sessions.AbstractSession session)` INTERNAL: Initialize the reference descriptor.
`boolean`	`isAggregateMapping()` INTERNAL: Related mapping should implement this method to return true.
`void`	`iterate(org.eclipse.persistence.internal.descriptors.DescriptorIterator iterator)` INTERNAL: Iterate on the appropriate attribute value.
`void`	`load(java.lang.Object object, org.eclipse.persistence.internal.queries.AttributeItem item, org.eclipse.persistence.internal.sessions.AbstractSession session, boolean fromFetchGroup)` Force instantiation of the load group.
`void`	`loadAll(java.lang.Object object, org.eclipse.persistence.internal.sessions.AbstractSession session, org.eclipse.persistence.internal.helper.IdentityHashSet loaded)` Force instantiation of all indirections.
`void`	`mergeChangesIntoObject(java.lang.Object target, org.eclipse.persistence.internal.sessions.ChangeRecord changeRecord, java.lang.Object source, org.eclipse.persistence.internal.sessions.MergeManager mergeManager, org.eclipse.persistence.internal.sessions.AbstractSession targetSession)` INTERNAL: Merge changes from the source to the target object.
`void`	`mergeIntoObject(java.lang.Object target, boolean isTargetUnInitialized, java.lang.Object source, org.eclipse.persistence.internal.sessions.MergeManager mergeManager, org.eclipse.persistence.internal.sessions.AbstractSession targetSession)` INTERNAL: Merge changes from the source to the target object.
`void`	`postDelete(DeleteObjectQuery query)` INTERNAL: The message is passed to its reference class descriptor.
`void`	`postDeleteAttributeValue(DeleteObjectQuery query, java.lang.Object attributeValue)` INTERNAL: The message is passed to its reference class descriptor.
`void`	`postInsert(WriteObjectQuery query)` INTERNAL: The message is passed to its reference class descriptor.
`void`	`postInsertAttributeValue(WriteObjectQuery query, java.lang.Object attributeValue)` INTERNAL: The message is passed to its reference class descriptor.
`void`	`postUpdate(WriteObjectQuery query)` INTERNAL: The message is passed to its reference class descriptor.
`void`	`postUpdateAttributeValue(WriteObjectQuery query, java.lang.Object attributeValue)` INTERNAL: The message is passed to its reference class descriptor.
`void`	`preDelete(DeleteObjectQuery query)` INTERNAL: The message is passed to its reference class descriptor.
`void`	`preDeleteAttributeValue(DeleteObjectQuery query, java.lang.Object attributeValue)` INTERNAL: The message is passed to its reference class descriptor.
`void`	`preInsert(WriteObjectQuery query)` INTERNAL: The message is passed to its reference class descriptor.
`void`	`preInsertAttributeValue(WriteObjectQuery query, java.lang.Object attributeValue)` INTERNAL: The message is passed to its reference class descriptor.
`void`	`preUpdate(WriteObjectQuery query)` INTERNAL: The message is passed to its reference class descriptor.
`void`	`preUpdateAttributeValue(WriteObjectQuery query, java.lang.Object attributeValue)` INTERNAL: The message is passed to its reference class descriptor.
`void`	`remoteInitialization(DistributedSession session)` INTERNAL: Once a descriptor is serialized to the remote session, all its mappings and reference descriptors are traversed.
`void`	`setReferenceClass(java.lang.Class aClass)` PUBLIC: This is a reference class whose instances this mapping will store in the domain objects.
`void`	`setReferenceClassName(java.lang.String aClassName)` INTERNAL: Used by MW.
`void`	`updateChangeRecord(java.lang.Object sourceClone, java.lang.Object newValue, java.lang.Object oldValue, org.eclipse.persistence.internal.sessions.ObjectChangeSet objectChangeSet, org.eclipse.persistence.internal.sessions.UnitOfWorkImpl uow)` INTERNAL: Either create a new change record or update the change record with the new value.
`boolean`	`verifyDelete(java.lang.Object object, org.eclipse.persistence.internal.sessions.AbstractSession session)` INTERNAL: Return whether the specified object and all its components have been deleted.

Methods inherited from class org.eclipse.persistence.mappings.DatabaseMapping
addUnconvertedProperty, buildBackupCloneForPartObject, buildChangeRecord, buildCloneForPartObject, buildContainerClone, buildObjectJoinExpression, buildObjectJoinExpression, buildShallowOriginalFromRow, calculateDeferredChanges, cascadeDiscoverAndPersistUnregisteredNewObjects, cascadePerformRemoveIfRequired, cascadePerformRemovePrivateOwnedObjectFromChangeSetIfRequired, cascadeRegisterNewIfRequired, clone, collectQueryParameters, createCloneValueHolder, derivesId, earlyPreDelete, fixRealObjectReferences, getAttributeAccessor, getAttributeClassification, getAttributeName, getAttributeValueFromObject, getContainerPolicy, getDerivedIdMapping, getDescriptor, getField, getFieldClassification, getFields, getGetMethodName, getMapsIdValue, getObjectCorrespondingTo, getOrderByNormalizedExpressions, getProperties, getProperty, getRealAttributeValueFromAttribute, getRealAttributeValueFromObject, getRealCollectionAttributeValueFromObject, getRelationshipPartner, getSelectFields, getSelectTables, getSetMethodName, getUnconvertedProperties, getValueFromRemoteValueHolder, getWeight, hasConstraintDependency, hasDependency, hasInverseConstraintDependency, hasMapsIdValue, hasUnconvertedProperties, instantiateAttribute, isAbstractColumnMapping, isAbstractCompositeCollectionMapping, isAbstractCompositeDirectCollectionMapping, isAbstractCompositeObjectMapping, isAbstractDirectMapping, isAggregateCollectionMapping, isAggregateObjectMapping, isAttributeValueFromObjectInstantiated, isCacheable, isCandidateForPrivateOwnedRemoval, isCascadedLockingSupported, isChangeTrackingSupported, isCloningRequired, isCollectionMapping, isDatabaseMapping, isDirectCollectionMapping, isDirectMapMapping, isDirectToFieldMapping, isDirectToXMLTypeMapping, isEISMapping, isElementCollectionMapping, isForeignReferenceMapping, isInAndOutSopObject, isInOnlySopObject, isInSopObject, isJoiningSupported, isJPAId, isLazy, isLockableMapping, isManyToManyMapping, isManyToOneMapping, isMapKeyMapping, isMultitenantPrimaryKeyMapping, isNestedTableMapping, isObjectReferenceMapping, isOneToManyMapping, isOneToOneMapping, isOptional, isOutOnlySopObject, isOutSopObject, isOwned, isPrimaryKeyMapping, isPrivateOwned, isReadOnly, isReferenceMapping, isRelationalMapping, isStructureMapping, isTransformationMapping, isUnidirectionalOneToManyMapping, isUsingMethodAccess, isVariableOneToOneMapping, isWriteOnly, isXMLMapping, iterateOnRealAttributeValue, performDataModificationEvent, postCalculateChanges, postCalculateChangesOnDeleted, postInitialize, postInitializeSourceAndTargetExpressions, preInitialize, prepareCascadeLockingPolicy, readFromResultSetIntoObject, readFromRowIntoObject, readOnly, readWrite, recordPrivateOwnedRemovals, rehashFieldDependancies, replaceValueHoldersIn, setAttributeAccessor, setAttributeName, setAttributeValueInObject, setChangeListener, setDerivedIdMapping, setDerivesId, setDescriptor, setGetMethodName, setIsCacheable, setIsInAndOutSopObject, setIsInSopObject, setIsJPAId, setIsLazy, setIsMapKeyMapping, setIsOptional, setIsOutSopObject, setIsPrimaryKeyMapping, setIsReadOnly, setMapsIdValue, setProperties, setProperty, setRealAttributeValueInObject, setSetMethodName, setWeight, simpleAddToCollectionChangeRecord, simpleRemoveFromCollectionChangeRecord, toString, updateCollectionChangeRecord, validateAfterInitialization, validateBeforeInitialization, valueFromObject, valueFromResultSet, valueFromRow, valueFromRow, writeFromAttributeIntoRow, writeFromObjectIntoRow, writeFromObjectIntoRowForShallowInsert, writeFromObjectIntoRowForShallowInsertWithChangeRecord, writeFromObjectIntoRowForUpdate, writeFromObjectIntoRowForUpdateAfterShallowInsert, writeFromObjectIntoRowForUpdateBeforeShallowDelete, writeFromObjectIntoRowForWhereClause, writeFromObjectIntoRowWithChangeRecord, writeInsertFieldsIntoRow, writeUpdateFieldsIntoRow

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail
- AggregateMapping
```
public AggregateMapping()
```
  Default constructor.

Method Detail

buildBackupClone

public void buildBackupClone(java.lang.Object clone,
                    java.lang.Object backup,
                    org.eclipse.persistence.internal.sessions.UnitOfWorkImpl unitOfWork)

INTERNAL: Clone the attribute from the clone and assign it to the backup.

Specified by:: buildBackupClone in class DatabaseMapping

buildClone

public void buildClone(java.lang.Object original,
              org.eclipse.persistence.internal.identitymaps.CacheKey cacheKey,
              java.lang.Object clone,
              java.lang.Integer refreshCascade,
              org.eclipse.persistence.internal.sessions.AbstractSession cloningSession)

INTERNAL: Clone the attribute from the original and assign it to the clone.

Specified by:: buildClone in class DatabaseMapping

buildCloneFromRow
```
public void buildCloneFromRow(org.eclipse.persistence.internal.sessions.AbstractRecord databaseRow,
                     org.eclipse.persistence.internal.queries.JoinedAttributeManager joinManager,
                     java.lang.Object clone,
                     org.eclipse.persistence.internal.identitymaps.CacheKey sharedCacheKey,
                     ObjectBuildingQuery sourceQuery,
                     org.eclipse.persistence.internal.sessions.UnitOfWorkImpl unitOfWork,
                     org.eclipse.persistence.internal.sessions.AbstractSession executionSession)
```
INTERNAL: A combination of readFromRowIntoObject and buildClone.
buildClone assumes the attribute value exists on the original and can simply be copied.

readFromRowIntoObject assumes that one is building an original.

Both of the above assumptions are false in this method, and actually attempts to do both at the same time.

Extract value from the row and set the attribute to this value in the working copy clone. In order to bypass the shared cache when in transaction a UnitOfWork must be able to populate working copies directly from the row.

Specified by:

buildCloneFromRow in class DatabaseMapping

buildCopy
```
public void buildCopy(java.lang.Object copy,
             java.lang.Object original,
             CopyGroup group)
```
INTERNAL: Copy of the attribute of the object. This is NOT used for unit of work but for templatizing an object.

Overrides:

buildCopy in class DatabaseMapping

buildExpression

public Expression buildExpression(java.lang.Object queryObject,
                         QueryByExamplePolicy policy,
                         Expression expressionBuilder,
                         java.util.Map processedObjects,
                         org.eclipse.persistence.internal.sessions.AbstractSession session)

INTERNAL: In case Query By Example is used, this method generates an expression from a attribute value pair. Since this is an Aggregate mapping, a recursive call is made to the buildExpressionFromExample method of ObjectBuilder.

Overrides:: buildExpression in class DatabaseMapping

compareForChange

public org.eclipse.persistence.internal.sessions.ChangeRecord compareForChange(java.lang.Object clone,
                                                                      java.lang.Object backup,
                                                                      org.eclipse.persistence.internal.sessions.ObjectChangeSet owner,
                                                                      org.eclipse.persistence.internal.sessions.AbstractSession session)

INTERNAL: Compare the changes between two aggregates. Return a change record holding the changes.

Specified by:: compareForChange in class DatabaseMapping
Returns:: prototype.changeset.ChangeRecord

compareObjects

public boolean compareObjects(java.lang.Object firstObject,
                     java.lang.Object secondObject,
                     org.eclipse.persistence.internal.sessions.AbstractSession session)

INTERNAL: Compare the attributes belonging to this mapping for the objects.

Specified by:: compareObjects in class DatabaseMapping

convertClassNamesToClasses
```
public void convertClassNamesToClasses(java.lang.ClassLoader classLoader)
```
INTERNAL: Convert all the class-name-based settings in this mapping to actual class-based settings. This method is used when converting a project that has been built with class names to a project with classes.

Overrides:

convertClassNamesToClasses in class DatabaseMapping

Parameters:

classLoader -

fixObjectReferences

public void fixObjectReferences(java.lang.Object object,
                       java.util.Map objectDescriptors,
                       java.util.Map processedObjects,
                       ObjectLevelReadQuery query,
                       DistributedSession session)

INTERNAL: An object has been serialized from the server to the remote client. Replace the transient attributes of the remote value holders with client-side objects.

Specified by:: fixObjectReferences in class DatabaseMapping

getReferenceClass
```
public java.lang.Class getReferenceClass()
```
PUBLIC: Returns the reference class

getReferenceClassName

public java.lang.String getReferenceClassName()

INTERNAL: Used by MW.

getReferenceDescriptor
```
public ClassDescriptor getReferenceDescriptor()
```
INTERNAL: Return the referenceDescriptor. This is a descriptor which is associated with the reference class. NOTE: If you are looking for the descriptor for a specific aggregate object, use #getReferenceDescriptor(Object). This will ensure you get the right descriptor if the object's descriptor is part of an inheritance tree.

Overrides:

getReferenceDescriptor in class DatabaseMapping

hasNestedIdentityReference
```
public boolean hasNestedIdentityReference()
```
INTERNAL: Indicates whether the mapping (or at least one of its nested mappings, at any nested depth) references an entity. To return true the mapping (or nested mapping) should be ForeignReferenceMapping with non-null and non-aggregate reference descriptor.

Overrides:

hasNestedIdentityReference in class DatabaseMapping

initialize

public void initialize(org.eclipse.persistence.internal.sessions.AbstractSession session)
                throws DescriptorException

INTERNAL: Initialize the reference descriptor.

Overrides:: initialize in class DatabaseMapping
Throws:: DescriptorException

isAggregateMapping
```
public boolean isAggregateMapping()
```
INTERNAL: Related mapping should implement this method to return true.

Overrides:

isAggregateMapping in class DatabaseMapping

iterate
```
public void iterate(org.eclipse.persistence.internal.descriptors.DescriptorIterator iterator)
```
INTERNAL: Iterate on the appropriate attribute value.

Specified by:

iterate in class DatabaseMapping

load

public void load(java.lang.Object object,
        org.eclipse.persistence.internal.queries.AttributeItem item,
        org.eclipse.persistence.internal.sessions.AbstractSession session,
        boolean fromFetchGroup)

Force instantiation of the load group.

Overrides:: load in class DatabaseMapping

loadAll

public void loadAll(java.lang.Object object,
           org.eclipse.persistence.internal.sessions.AbstractSession session,
           org.eclipse.persistence.internal.helper.IdentityHashSet loaded)

Force instantiation of all indirections.

Overrides:: loadAll in class DatabaseMapping

mergeChangesIntoObject
```
public void mergeChangesIntoObject(java.lang.Object target,
                          org.eclipse.persistence.internal.sessions.ChangeRecord changeRecord,
                          java.lang.Object source,
                          org.eclipse.persistence.internal.sessions.MergeManager mergeManager,
                          org.eclipse.persistence.internal.sessions.AbstractSession targetSession)
```
INTERNAL: Merge changes from the source to the target object. With aggregates the merge must cascade to the object changes for the aggregate object because aggregate objects have no identity outside of themselves. The actual aggregate object does not need to be replaced, because even if the clone references another aggregate it appears the same to TopLink

Specified by:

mergeChangesIntoObject in class DatabaseMapping

mergeIntoObject

public void mergeIntoObject(java.lang.Object target,
                   boolean isTargetUnInitialized,
                   java.lang.Object source,
                   org.eclipse.persistence.internal.sessions.MergeManager mergeManager,
                   org.eclipse.persistence.internal.sessions.AbstractSession targetSession)

INTERNAL: Merge changes from the source to the target object. This merge is only called when a changeSet for the target does not exist or the target is uninitialized

Specified by:: mergeIntoObject in class DatabaseMapping

postDelete
```
public void postDelete(DeleteObjectQuery query)
                throws DatabaseException,
                       OptimisticLockException
```
INTERNAL: The message is passed to its reference class descriptor.

Overrides:

postDelete in class DatabaseMapping

Throws:

DatabaseException

OptimisticLockException