net.ontopia.persistence.proxy

Interface StorageAccessIF

All Known Implementing Classes:

RDBMSAccess

public interface StorageAccessIF

INTERNAL: Interface that encapsulates the access to the actual data repository.

Method Summary

Modifier and Type	Method and Description
void	abort() INTERNAL: Aborts all changes performed in the transaction.
void	close() INTERNAL: Closes the storage access, which allows it to free its resources.
void	commit() INTERNAL: Commits the changes performed in the transaction.
void	createObject(ObjectAccessIF oaccess, Object object) INTERNAL: Called by the transaction when it requests the new object to be created in the data repository.
QueryIF	createQuery(JDOQuery jdoquery, ObjectAccessIF oaccess, AccessRegistrarIF registrar, boolean lookup_identities) INTERNAL: Build a QueryIF from the specified JDO query instance.
QueryIF	createQuery(String name, ObjectAccessIF oaccess, AccessRegistrarIF registrar) INTERNAL: Creates a query instance for the given transaction.
void	deleteObject(ObjectAccessIF oaccess, Object object) INTERNAL: Called by the transaction when it requests the object to be deleted in the data repository.
void	flush() INTERNAL: Called when the transaction requires the transaction changes to be stored by the storage access (i.e.
IdentityIF	generateIdentity(Class<?> type) INTERNAL: Called by the application when it requests a new object identity for a given object type.
String	getId() INTERNAL: Gets the storage access id.
String	getProperty(String property) INTERNAL: Gets the value of the specified property.
StorageIF	getStorage() INTERNAL: Returns the storage definition that the access uses.
boolean	isReadOnly() INTERNAL: Returns true if the storage access is read-only.
Object	loadField(AccessRegistrarIF registrar, IdentityIF identity, int field) INTERNAL: Requests the loading of the specified field for the given object identity.
Object	loadFieldMultiple(AccessRegistrarIF registrar, Collection<IdentityIF> identities, IdentityIF current, Class<?> type, int field) INTERNAL: Requests the loading of the specified field for all the given object identities.
boolean	loadObject(AccessRegistrarIF registrar, IdentityIF identity) INTERNAL: Check for the existence of the object identity in the data repository.
void	storeDirty(ObjectAccessIF oaccess, Object object) INTERNAL: Stores object fields that are dirty in the database.
boolean	validate() INTERNAL: Returns true if the storage access is valid.

Method Detail

getId

String getId()

INTERNAL: Gets the storage access id. This id is unique for a given StorageIF instance.

getStorage

StorageIF getStorage()

INTERNAL: Returns the storage definition that the access uses.

isReadOnly

boolean isReadOnly()

INTERNAL: Returns true if the storage access is read-only.

getProperty

String getProperty(String property)

INTERNAL: Gets the value of the specified property.

validate

boolean validate()

INTERNAL: Returns true if the storage access is valid.

commit

void commit()

INTERNAL: Commits the changes performed in the transaction.

abort

void abort()

INTERNAL: Aborts all changes performed in the transaction.

close

void close()

INTERNAL: Closes the storage access, which allows it to free its resources.

flush

void flush()

INTERNAL: Called when the transaction requires the transaction changes to be stored by the storage access (i.e. written to the database).

This method exists mainly to allow storage access implementations to optimize its communication with data repositories. An example of this is writing transaction changes in batches to improve performance.

Note that the transaction will always call this method at the end of its store method. It will do this so that it is sure that the changes will be visible inside the data repository.

loadObject

boolean loadObject(AccessRegistrarIF registrar,
                   IdentityIF identity)

INTERNAL: Check for the existence of the object identity in the data repository. An exception will be thrown if the object does not exist. If it exists the access registrar will be notified.

Returns:

true if object was found in the data store, false otherwise.

loadField

Object loadField(AccessRegistrarIF registrar,
                 IdentityIF identity,
                 int field)
          throws IdentityNotFoundException

INTERNAL: Requests the loading of the specified field for the given object identity. An exception will be thrown if the object does not exist. If it exists the access registrar will be notified.

Returns:

The value loaded for the specific field. Note that if the field is a reference field the identity will be returned, not the actual object. This is because the storage system does not deal with persistent object instances directly.

Throws:

IdentityNotFoundException - if the identity was not found.

loadFieldMultiple

Object loadFieldMultiple(AccessRegistrarIF registrar,
                         Collection<IdentityIF> identities,
                         IdentityIF current,
                         Class<?> type,
                         int field)
                  throws IdentityNotFoundException

INTERNAL: Requests the loading of the specified field for all the given object identities. An exception will be thrown if the current object does not exist. If it exists the access registrar will be notified.

Returns:

The value loaded for the specific field. Note that if the field is a reference field the identity will be returned, not the actual object. This is because the storage system does not deal with persistent object instances directly.

Throws:

IdentityNotFoundException - if the identity was not found.

createObject

void createObject(ObjectAccessIF oaccess,
                  Object object)

INTERNAL: Called by the transaction when it requests the new object to be created in the data repository. The ObjectAccessIF object is used to access information about the object as needed.

deleteObject

void deleteObject(ObjectAccessIF oaccess,
                  Object object)

INTERNAL: Called by the transaction when it requests the object to be deleted in the data repository.

storeDirty

void storeDirty(ObjectAccessIF oaccess,
                Object object)

INTERNAL: Stores object fields that are dirty in the database.

generateIdentity

IdentityIF generateIdentity(Class<?> type)

INTERNAL: Called by the application when it requests a new object identity for a given object type.

createQuery

QueryIF createQuery(String name,
                    ObjectAccessIF oaccess,
                    AccessRegistrarIF registrar)

INTERNAL: Creates a query instance for the given transaction.

createQuery

QueryIF createQuery(JDOQuery jdoquery,
                    ObjectAccessIF oaccess,
                    AccessRegistrarIF registrar,
                    boolean lookup_identities)

INTERNAL: Build a QueryIF from the specified JDO query instance.