Module org.eclipse.persistence.core

Package org.eclipse.persistence.queries

Class CursorPolicy

java.lang.Object

org.eclipse.persistence.internal.queries.ContainerPolicy

org.eclipse.persistence.queries.CursorPolicy

All Implemented Interfaces:

Serializable, Cloneable, CoreContainerPolicy<AbstractSession>

Direct Known Subclasses:

CursoredStreamPolicy, ScrollableCursorPolicy

public abstract class CursorPolicy
extends ContainerPolicy

Purpose: Abstract class for all Cursor-related policy objects

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
protected int	pageSize
protected ReadQuery	query

Fields inherited from class org.eclipse.persistence.internal.queries.ContainerPolicy

constructor, defaultContainerClass, elementDescriptor

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	CursorPolicy()	INTERNAL: default constructor
protected	CursorPolicy(ReadQuery query, int pageSize)	INTERNAL:

Method Summary

Modifier and Type	Method	Description
ContainerPolicy	clone(ReadQuery query)	INTERNAL:
CollectionChangeEvent	createChangeEvent(Object collectionOwner, String propertyName, Object collectionChanged, Object elementChanged, int changeType, Integer index, boolean isChangeApplied)	INTERNAL: Creates a CollectionChangeEvent for the container
abstract Object	execute()	INTERNAL: Execute the cursored select and build the stream.
int	getPageSize()	Return the number of elements to be read into a cursored stream when more elements are needed from the database.
ReadQuery	getQuery()	INTERNAL: Return the query.
boolean	hasNext(Object iterator)	INTERNAL: Return whether the iterator has more objects.
boolean	isCursorPolicy()
Object	iteratorFor(Object container)	INTERNAL: Return an iterator for the given container.
protected Object	next(Object iterator)	INTERNAL: Return the next object on the queue.
boolean	overridesRead()	INTERNAL: This can be used by collection such as cursored stream to gain control over execution.
void	prepare(DatabaseQuery query, AbstractSession session)	INTERNAL: Prepare and validate.
abstract Object	remoteExecute()	INTERNAL: Execute the cursored select and build the stream.
void	setPageSize(int pageSize)	Set the number of elements to be read into a cursored stream when more elements are needed from the database.
void	setQuery(ReadQuery query)	INTERNAL: Set the query.
int	sizeFor(Object container)	INTERNAL: Return the size of container.
protected Object	toStringInfo()

Methods inherited from class org.eclipse.persistence.internal.queries.ContainerPolicy

addAdditionalFieldsToQuery, addAll, addAll, addFieldsForMapKey, addInto, addInto, addInto, addInto, addNestedJoinsQueriesForMapKey, addNextValueFromIteratorInto, buildChangeSetForNewObjectInCollection, buildCloneForKey, buildCollectionEntry, buildContainerFromVector, buildDefaultPolicy, buildKey, buildKeyFromJoinedRow, buildPolicyFor, buildPolicyFor, buildReferencesPKList, buildSelectionQueryForDirectCollectionMapping, cascadeDiscoverAndPersistUnregisteredNewObjects, cascadePerformRemoveIfRequired, cascadeRegisterNewIfRequired, clear, clone, cloneFor, collectObjectForNewCollection, compareCollectionsForChange, compareKeys, concatenateContainers, containerInstance, containerInstance, contains, contains, convertClassNamesToClasses, copyMapDataToRow, createChangeSetForKeys, createWrappedObjectFromExistingWrappedObject, deleteWrappedObject, equals, getAdditionalFieldsForJoin, getAdditionalTablesForJoinQuery, getChangeValuesFrom, getCloneDataFromChangeSet, getConstructor, getContainerClass, getContainerClassName, getDefaultContainerClass, getDescriptorForMapKey, getElementDescriptor, getIdentityFieldsForMapKey, getKeyMappingDataForWriteQuery, getKeySelectionCriteria, getKeyType, hasElementDescriptor, hashCode, hasOrder, initialize, initializeConstructor, isCollectionPolicy, isCursoredStreamPolicy, isDirectMapPolicy, isEmpty, isListPolicy, isMapKeyObject, isMappedKeyMapPolicy, isMapPolicy, isOrderedListPolicy, isScrollableCursorPolicy, isValidContainer, isValidContainerType, iterateOnMapKey, keyFrom, keyFromEntry, keyFromIterator, mergeCascadeParts, mergeChanges, mergeChanges, next, nextEntry, nextEntry, postCalculateChanges, postCalculateChanges, postInitialize, prepareForExecution, processAdditionalWritableMapKeyFields, propagatesEventsToCollection, propogatePostDelete, propogatePostInsert, propogatePostUpdate, propogatePreDelete, propogatePreInsert, propogatePreUpdate, recordAddToCollectionInChangeRecord, recordPrivateOwnedRemovals, recordRemoveFromCollectionInChangeRecord, recordUpdateToCollectionInChangeRecord, removeFrom, removeFrom, removeFrom, requiresDataModificationEvents, setConstructor, setContainerClass, setContainerClassName, setDefaultContainerClass, setElementDescriptor, setKeyName, setKeyName, shouldAddAll, shouldIncludeKeyInDeleteEvent, shouldUpdateForeignKeysPostInsert, toString, unwrapElement, unwrapIteratorResult, updateChangeRecordForSelfMerge, updateJoinedMappingIndexesForMapKey, valueFromPKList, vectorFor

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Field Details

pageSize

protected int pageSize

query

protected ReadQuery query

Constructor Details

CursorPolicy

protected CursorPolicy()

INTERNAL: default constructor

CursorPolicy

protected CursorPolicy(ReadQuery query,
 int pageSize)

INTERNAL:

Method Details

clone

public ContainerPolicy clone(ReadQuery query)

INTERNAL:

Overrides:

clone in class ContainerPolicy

createChangeEvent

public CollectionChangeEvent createChangeEvent(Object collectionOwner,
 String propertyName,
 Object collectionChanged,
 Object elementChanged,
 int changeType,
 Integer index,
 boolean isChangeApplied)

INTERNAL: Creates a CollectionChangeEvent for the container

Specified by:

createChangeEvent in class ContainerPolicy

execute

public abstract Object execute()

INTERNAL: Execute the cursored select and build the stream.

Overrides:

execute in class ContainerPolicy

getPageSize

public int getPageSize()

Return the number of elements to be read into a cursored stream when more elements are needed from the database.

getQuery

public ReadQuery getQuery()

INTERNAL: Return the query.

hasNext

public boolean hasNext(Object iterator)

INTERNAL: Return whether the iterator has more objects.

Specified by:

hasNext in interface CoreContainerPolicy<AbstractSession>

Specified by:

hasNext in class ContainerPolicy

Parameters:

iterator - java.lang.Object

Returns:

boolean true if iterator has more objects

See Also:

• ContainerPolicy.iteratorFor(java.lang.Object)

isCursorPolicy

public boolean isCursorPolicy()

Overrides:

isCursorPolicy in class ContainerPolicy

iteratorFor

public Object iteratorFor(Object container)

INTERNAL: Return an iterator for the given container. This iterator can then be used as a parameter to #hasNext() and #next().

Specified by:

iteratorFor in interface CoreContainerPolicy<AbstractSession>

Specified by:

iteratorFor in class ContainerPolicy

See Also:

• ContainerPolicy.hasNext(java.lang.Object)
• ContainerPolicy.next(java.lang.Object)

next

protected Object next(Object iterator)

INTERNAL: Return the next object on the queue. The iterator is the one returned from #iteratorFor().

Specified by:

next in class ContainerPolicy

See Also:

• ContainerPolicy.iteratorFor(java.lang.Object)

overridesRead

public boolean overridesRead()

INTERNAL: This can be used by collection such as cursored stream to gain control over execution.

Overrides:

overridesRead in class ContainerPolicy

prepare

public void prepare(DatabaseQuery query,
 AbstractSession session)
             throws QueryException

INTERNAL: Prepare and validate.

Overrides:

prepare in class ContainerPolicy

Throws:

QueryException

remoteExecute

public abstract Object remoteExecute()

INTERNAL: Execute the cursored select and build the stream.

Overrides:

remoteExecute in class ContainerPolicy

setPageSize

public void setPageSize(int pageSize)

Set the number of elements to be read into a cursored stream when more elements are needed from the database.

setQuery

public void setQuery(ReadQuery query)

INTERNAL: Set the query.

sizeFor

public int sizeFor(Object container)

INTERNAL: Return the size of container.

Specified by:

sizeFor in interface CoreContainerPolicy<AbstractSession>

Overrides:

sizeFor in class ContainerPolicy

toStringInfo

protected Object toStringInfo()

Overrides:

toStringInfo in class ContainerPolicy