org.jpox.store.rdbms.scostore
Class AbstractCollectionStore

java.lang.Object
  org.jpox.store.rdbms.scostore.ElementContainerStore
      org.jpox.store.rdbms.scostore.AbstractCollectionStore

Direct Known Subclasses:

FKListStore, FKSetStore, JoinListStore, JoinSetStore, MapKeySetStore, MapValueSetStore

public abstract class AbstractCollectionStore
extends ElementContainerStore

Abstract representation of a store of a Collection. Contains all common parts of storing Sets and Lists.

Version:

$Revision: 1.44 $

Nested Class Summary

Nested classes/interfaces inherited from class org.jpox.store.rdbms.scostore.ElementContainerStore

ElementContainerStore.ElementInfo

Field Summary

protected java.lang.String	containsStmt Statement for getting whether an element is contained in the collection.
protected DatastoreAdapter	dba Datastore adapter in use by this store.
protected static Localiser	LOCALISER Localiser for messages.
protected AbstractPropertyMetaData	ownerFieldMetaData MetaData for the field in the owner with this container.
protected JavaTypeMapping	ownerMapping Mapping to the owner of the container.
protected StoreManager	storeMgr Manager for the store.
protected DatastoreIdentifier	thisIdentifier Identifier for the container in JDOQL queries.

Fields inherited from class org.jpox.store.rdbms.scostore.ElementContainerStore

clearStmt, clr, containerTable, elementInfo, elementMapping, elementsAreEmbedded, elementsAreSerialised, elementType, elmIdentifier, emd, iterateUsingDiscriminator, orderMapping, relationDiscriminatorMapping, relationDiscriminatorValue, sizeStmt

Constructor Summary

protected

AbstractCollectionStore(StoreManager storeMgr, ClassLoaderResolver clr) Constructor.

Method Summary

boolean	contains(StateManager sm, java.lang.Object element) Method to verify if the association owner vs elements contains a specific element in the association
protected java.sql.ResultSet	executeQuery(java.lang.String stmt, java.sql.PreparedStatement ps) Method to execute a PreparedStatement query, and return the ResultSet.
protected int	executeUpdate(java.lang.String stmt, java.sql.PreparedStatement ps) Method to execute a PreparedStatement.
protected java.lang.String	getContainsStmt() Generate statement for retrieving the contents of the Collection.
QueryExpression	getExistsSubquery(QueryExpression qs, JavaTypeMapping mapping, LogicSetExpression ownerTe, DatastoreIdentifier collectionRangeVar) JDOQL utility to generate an exists() statement for an element.
JavaTypeMapping	getOwnerMapping() Accessor for the owner mapping.
QueryExpression	getSizeSubquery(QueryExpression qs, JavaTypeMapping mapping, LogicSetExpression ownerTe, DatastoreIdentifier collectionRangeVar) JDOQL utility to generate a subquery for the size() of the collection.
protected StateManager	getStateManagerForEmbeddedPCObject(StateManager sm, java.lang.Object obj, JoinTable table) Method to return the StateManager for an embedded PC object (element, key, value).
StoreManager	getStoreManager() Accessor for the RDBMSManager.
protected java.lang.String	getUpdateEmbeddedElementStmt(JavaTypeMapping fieldMapping) Generate statement for update the field of an embedded element.
protected void	initialiseStatements() Method to initialise the statements being used.
protected boolean	isEmbeddedMapping(JavaTypeMapping mapping) Check if the mapping correspond to a non pc object or embedded field
protected int	populateOwnerInStatement(StateManager sm, PersistenceManager pm, java.sql.PreparedStatement ps, int jdbcPosition) Convenience method to populate the passed PreparedStatement with the value from the owner.
boolean	updateEmbeddedElement(StateManager sm, java.lang.Object element, int fieldNumber, java.lang.Object value) Method to update a field of an embedded element.

Methods inherited from class org.jpox.store.rdbms.scostore.ElementContainerStore

clear, getAddStmt, getClearStmt, getElementInformationForClass, getElementType, getSizeStmt, hasOrderMapping, iterator, newResultObjectFactory, populateElementDiscriminatorInStatement, populateElementInStatement, populateEmbeddedElementFieldsInStatement, populateOrderInStatement, populateRelationDiscriminatorInStatement, size, validateElementForReading, validateElementForWriting, validateElementType

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

containsStmt

protected java.lang.String containsStmt

Statement for getting whether an element is contained in the collection.

LOCALISER

protected static final Localiser LOCALISER

Localiser for messages.

storeMgr

protected StoreManager storeMgr

Manager for the store.

dba

protected DatastoreAdapter dba

Datastore adapter in use by this store.

ownerMapping

protected JavaTypeMapping ownerMapping

Mapping to the owner of the container.

ownerFieldMetaData

protected AbstractPropertyMetaData ownerFieldMetaData

MetaData for the field in the owner with this container.

thisIdentifier

protected final DatastoreIdentifier thisIdentifier

Identifier for the container in JDOQL queries.

Constructor Detail

AbstractCollectionStore

protected AbstractCollectionStore(StoreManager storeMgr,
                                  ClassLoaderResolver clr)

Constructor.

Parameters:

storeMgr - Manager for the store

clr - ClassLoader resolver

Method Detail

initialiseStatements

protected void initialiseStatements()

Method to initialise the statements being used.

Overrides:

initialiseStatements in class ElementContainerStore

getUpdateEmbeddedElementStmt

protected java.lang.String getUpdateEmbeddedElementStmt(JavaTypeMapping fieldMapping)

Generate statement for update the field of an embedded element.

 UPDATE SETTABLE
 SET EMBEDDEDFIELD1 = ?
 WHERE OWNERCOL=?
 AND ELEMENTCOL = ?
 

Parameters:

fieldMapping - The mapping for the field within the embedded object to be updated

Returns:

Statement for updating an embedded element in the Set

updateEmbeddedElement

public boolean updateEmbeddedElement(StateManager sm,
                                     java.lang.Object element,
                                     int fieldNumber,
                                     java.lang.Object value)

Method to update a field of an embedded element.

Parameters:

sm - State Manager of the owner

element - The element to update

fieldNumber - The number of the field to update

value - The value

Returns:

true if the datastore was updated

getContainsStmt

protected java.lang.String getContainsStmt()

Generate statement for retrieving the contents of the Collection. The discriminator part is only present when the element type has inheritance strategy of "superclass-table" and is Inverse.

 SELECT OWNERCOL FROM COLLECTIONTABLE 
 WHERE OWNERCOL=?
 AND ELEMENTCOL=?
 [AND DISCRIMINATOR=?]
 [AND RELATION_DISCRIM=?]
 

Returns:

Statement for retrieving the contents of the Collection.

contains

public boolean contains(StateManager sm,
                        java.lang.Object element)

Method to verify if the association owner vs elements contains a specific element in the association

Parameters:

sm - The StateManager

element - The element

Returns:

Whether it contains the element

getExistsSubquery

public QueryExpression getExistsSubquery(QueryExpression qs,
                                         JavaTypeMapping mapping,
                                         LogicSetExpression ownerTe,
                                         DatastoreIdentifier collectionRangeVar)

JDOQL utility to generate an exists() statement for an element. The generated query will be of the form

 SELECT 1 FROM JOINTABLE THIS_JOIN WHERE THIS_JOIN.OWNER_ID_OID = THIS.OWNER_ID
 

Parameters:

qs - The JDOQL query statement

mapping - mapping of the field

ownerTe - Expression for the table

collectionRangeVar - range variable for the collection

Returns:

The JDOQL query statement

getSizeSubquery

public QueryExpression getSizeSubquery(QueryExpression qs,
                                       JavaTypeMapping mapping,
                                       LogicSetExpression ownerTe,
                                       DatastoreIdentifier collectionRangeVar)

JDOQL utility to generate a subquery for the size() of the collection. The generated query will be of the form

 SELECT COUNT(*) FROM JOINTABLE THIS_JOIN WHERE THIS_JOIN.OWNER_ID_OID = THIS.OWNER_ID
 

Parameters:

qs - The JDOQL query statement

mapping - mapping of the field

ownerTe - Expression for the table

collectionRangeVar - range variable for the collection

Returns:

The JDOQL query statement

getStoreManager

public StoreManager getStoreManager()

Accessor for the RDBMSManager.

Returns:

The RDBMSManager.

getOwnerMapping

public JavaTypeMapping getOwnerMapping()

Accessor for the owner mapping.

Returns:

Owner mapping.

executeUpdate

protected int executeUpdate(java.lang.String stmt,
                            java.sql.PreparedStatement ps)
                     throws java.sql.SQLException

Method to execute a PreparedStatement. Prints logging information about timings.

Parameters:

stmt - The statement text

ps - The Prepared Statement

Returns:

The numer of rows affected (as per PreparedStatement.executeUpdate)

Throws:

java.sql.SQLException - Thrown if an error occurs

executeQuery

protected java.sql.ResultSet executeQuery(java.lang.String stmt,
                                          java.sql.PreparedStatement ps)
                                   throws java.sql.SQLException

Method to execute a PreparedStatement query, and return the ResultSet. Prints logging information about timings.

Parameters:

stmt - The statement text

ps - The Prepared Statement

Returns:

The ResultSet from the query

Throws:

java.sql.SQLException - Thrown if an error occurs

isEmbeddedMapping

protected boolean isEmbeddedMapping(JavaTypeMapping mapping)

Check if the mapping correspond to a non pc object or embedded field

Parameters:

mapping - the mapping

Returns:

true if the field is embedded into one column

populateOwnerInStatement

protected int populateOwnerInStatement(StateManager sm,
                                       PersistenceManager pm,
                                       java.sql.PreparedStatement ps,
                                       int jdbcPosition)

Convenience method to populate the passed PreparedStatement with the value from the owner.

Parameters:

sm - State Manager

pm - Persistence Manager

ps - The PreparedStatement

jdbcPosition - Position in JDBC statement to populate

Returns:

The next position in the JDBC statement

getStateManagerForEmbeddedPCObject

protected StateManager getStateManagerForEmbeddedPCObject(StateManager sm,
                                                          java.lang.Object obj,
                                                          JoinTable table)

Method to return the StateManager for an embedded PC object (element, key, value). It creates one if the element is not currently managed.

Parameters:

sm - State Manager of the owner

obj - The embedded PC object

table - Join table where the objects are stored

Returns:

The state manager