org.datanucleus.store
Class AbstractStoreManager

java.lang.Object
  org.datanucleus.store.AbstractStoreManager

All Implemented Interfaces:

StoreManager

Direct Known Subclasses:

MappedStoreManager

public abstract class AbstractStoreManager
extends java.lang.Object
implements StoreManager

An abstract representation of a Store Manager. Manages the persistence of objects to the store. Will be implemented for the type of datastore (RDBMS, ODBMS, OLAP) in question. The store manager's responsibilities include:

• Creating and/or validating datastore tables according to the persistent classes being accessed by the application.
• Serving as the primary intermediary between StateManagers and the database.
• Serving as the base Extent and Query factory.

A store manager's knowledge of its contents is typically not complete. It knows about the classes that it has encountered in its lifetime. The PersistenceManager can make the StoreManager aware of a class, and can check if the StoreManager knows about a particular class. The Auto-Start mechanism provides a way of inheriting knowledge from the last time the store was used.

Field Summary

protected java.lang.String	autoStartMechanism Name of the AutoStart mechanism.
protected ConnectionManager	connectionMgr ConnectionManager
protected boolean	fixedDatastore Whether this datastore is fixed (no mods to datastore classes allowed).
protected static Localiser	LOCALISER Localiser for messages.
protected java.lang.String	nontxConnectionFactoryName Name of non-transactional connection factory (null if not present).
protected OMFContext	omfContext ObjectManagerFactory context.
protected StorePersistenceHandler	persistenceHandler2 Persistence handler.
protected boolean	readOnlyDatastore Whether this datastore is read only.
protected StoreSchemaHandler	schemaHandler Schema handler.
protected AutoStartMechanism	starter Auto-Start mechanism to use.
protected boolean	starterInitialised Whether the AutoStart mechanism is initialised
protected StoreDataManager	storeDataMgr Manager for the data definition in the datastore.
protected java.lang.String	storeManagerKey Key for this StoreManager e.g "rdbms", "db4o"
protected StoreManagerRuntime	storeManagerRuntime StoreManager Runtime.
protected java.lang.String	txConnectionFactoryName Name of transactional connection factory.
protected ValueGenerationManager	valueGenerationMgr Manager for value generation.

Constructor Summary

protected

AbstractStoreManager(java.lang.String key, ClassLoaderResolver clr, OMFContext omfContext) Constructor for a new StoreManager.

Method Summary

void	addClass(java.lang.String className, ClassLoaderResolver clr) Method to add a class to the managed list for this datastore manager.
void	addClasses(java.lang.String[] classNames, ClassLoaderResolver clr) Add classes to the persistence model for the datastore.
void	assertReadOnlyForUpdateOfObject(ObjectProvider op) Convenience method to assert when this StoreManager is read-only and the specified object is attempting to be updated.
protected void	clearAutoStarter() Method to clear the Auto-Starter status.
void	close() Release of resources.
protected void	deregisterAllStoreData() Method to deregister all existing store data so that we are managing nothing.
ApiAdapter	getApiAdapter() Accessor for the API adapter.
Store	getBackingStoreForField(ClassLoaderResolver clr, AbstractMemberMetaData fmd, java.lang.Class type) Accessor for the backing store for the specified field.
java.lang.String	getClassNameForObjectID(java.lang.Object id, ClassLoaderResolver clr, ExecutionContext ec) Returns the class corresponding to the given object identity.
ManagedConnection	getConnection(ExecutionContext ec) Accessor for a connection for the specified ObjectManager.
ManagedConnection	getConnection(ExecutionContext ec, java.util.Map options) Accessor for a connection for the specified ObjectManager.
ManagedConnection	getConnection(int isolation_level) Utility to return a non-transactional Connection.
java.lang.String	getConnectionDriverName() Convenience accessor for the driver name to use for the connection (if applicable for this datastore).
java.lang.Object	getConnectionFactory() Convenience accessor for the factory for the connection (transactional).
java.lang.Object	getConnectionFactory2() Convenience accessor for the factory for the connection (non-transactional).
java.lang.String	getConnectionFactory2Name() Convenience accessor for the factory name for the connection (non-transactional).
java.lang.String	getConnectionFactoryName() Convenience accessor for the factory name for the connection (transactional).
ConnectionManager	getConnectionManager() Accessor for the connection manager for this store manager.
java.lang.String	getConnectionPassword() Convenience accessor for the password to use for the connection.
java.lang.String	getConnectionURL() Convenience accessor for the URL for the connection
java.lang.String	getConnectionUserName() Convenience accessor for the username to use for the connection
java.util.Date	getDatastoreDate() Get the date/time of the datastore.
Extent	getExtent(ExecutionContext ec, java.lang.Class c, boolean subclasses) Interface to getting an Extent for a class.
MetaDataManager	getMetaDataManager()
NucleusConnection	getNucleusConnection(ExecutionContext ec) Method to return a connection for the ObjectManager.
NucleusSequence	getNucleusSequence(ExecutionContext ec, SequenceMetaData seqmd) Method to return a datastore sequence for this datastore matching the passed sequence MetaData.
OMFContext	getOMFContext() Accessor for the context in which this StoreManager is running
StorePersistenceHandler	getPersistenceHandler() Accessor for the store persistence handler.
protected java.util.Properties	getPropertiesForGenerator(AbstractClassMetaData cmd, int absoluteFieldNumber, ExecutionContext ec, SequenceMetaData seqmd, TableGeneratorMetaData tablegenmd) Method to return the properties to pass to the generator for the specified field.
java.lang.String	getQueryCacheKey() Accessor for the key used for representing this store manager in the query cache.
StoreManagerRuntime	getRuntimeManager() Accessor for the runtime management of this component (if specified as required to the PMF/EMF).
StoreSchemaHandler	getSchemaHandler() Accessor for the store schema handler (if this datastore supports the concept of a schema).
java.lang.String	getStoreManagerKey() Accessor for the key for this store manager.
protected java.lang.String	getStrategyForNative(AbstractClassMetaData cmd, int absFieldNumber) Method defining which value-strategy to use when the user specifies "native".
java.lang.Object	getStrategyValue(ExecutionContext ec, AbstractClassMetaData cmd, int absoluteFieldNumber) Method to retrieve the value for a strategy for a particular field.
protected java.lang.Object	getStrategyValueForGenerator(ValueGenerator generator, ExecutionContext ec) Accessor for the next value from the specified generator.
java.util.HashSet<java.lang.String>	getSubClassesForClass(java.lang.String className, boolean includeDescendents, ClassLoaderResolver clr) Utility to return the names of the classes that are known subclasses of the provided class.
java.util.Collection<java.lang.String>	getSupportedOptions() Accessor for the supported options in string form.
ValueGenerationManager	getValueGenerationManager() Accessor for the ValueGenerationManager for obtaining sequences.
protected void	initialiseAutoStart(ClassLoaderResolver clr) Method to initialise the auto-start mechanism, loading up the classes from its store into memory so that we start from where we got to last time.
boolean	isStrategyDatastoreAttributed(IdentityStrategy identityStrategy, boolean datastoreIdentityField) Method to return if a particular value strategy is attributed by the datastore.
protected void	logConfiguration() Convenience method to log the configuration of this store manager.
java.lang.String	manageClassForIdentity(java.lang.Object id, ClassLoaderResolver clr) Convenience method to ensure that the class defined by the passed OID/SingleFIeldIdentity is managed by the store.
boolean	managesClass(java.lang.String className) Accessor for whether the specified class is managed currently
protected StoreData	newStoreData(ClassMetaData cmd, ClassLoaderResolver clr) Instantiate a StoreData instance using the provided ClassMetaData and ClassLoaderResolver.
void	notifyObjectIsOutdated(ObjectProvider sm) Notifies this store manager that the main memory (RAM, heap) copy of the PC object of the supplied StateManager may not be regarded as valid anymore.
void	performVersionCheck(ObjectProvider sm, java.lang.Object versionDatastore, VersionMetaData versionMetaData) Perform an optimistic version check on the passed object, against the passed version in the datastore.
void	printInformation(java.lang.String category, java.io.PrintStream ps) Method to output the information about the StoreManager.
protected void	registerConnectionFactory() Register the Connection Factory defined in plugins
protected void	registerConnectionMgr() Register the default ConnectionManager implementation
protected void	registerStoreData(StoreData data) Method to register some data with the store.
void	removeAllClasses(ClassLoaderResolver clr) Remove all classes from the persistence model for the datastore.
boolean	supportsQueryLanguage(java.lang.String language) Accessor for whether this query language is supported.
boolean	supportsValueStrategy(java.lang.String strategy) Accessor for whether this value strategy is supported.
void	transactionCommitted(ExecutionContext ec) Method to inform the StoreManager that a transaction has committed for the specified execution context.
void	transactionRolledBack(ExecutionContext ec) Method to inform the StoreManager that a transaction has rolled back for the specified execution context.
void	transactionStarted(ExecutionContext ec) Method to inform the StoreManager that a transaction has started for the specified execution context.

Methods inherited from class java.lang.Object

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

Field Detail

LOCALISER

protected static final Localiser LOCALISER

Localiser for messages.

storeManagerKey

protected final java.lang.String storeManagerKey

Key for this StoreManager e.g "rdbms", "db4o"

readOnlyDatastore

protected final boolean readOnlyDatastore

Whether this datastore is read only.

fixedDatastore

protected final boolean fixedDatastore

Whether this datastore is fixed (no mods to datastore classes allowed).

starter

protected AutoStartMechanism starter

Auto-Start mechanism to use.

starterInitialised

protected boolean starterInitialised

Whether the AutoStart mechanism is initialised

omfContext

protected final OMFContext omfContext

ObjectManagerFactory context.

valueGenerationMgr

protected final ValueGenerationManager valueGenerationMgr

Manager for value generation.

storeManagerRuntime

protected StoreManagerRuntime storeManagerRuntime

StoreManager Runtime. Used when providing management of services.

storeDataMgr

protected StoreDataManager storeDataMgr

Manager for the data definition in the datastore.

autoStartMechanism

protected java.lang.String autoStartMechanism

Name of the AutoStart mechanism.

persistenceHandler2

protected StorePersistenceHandler persistenceHandler2

Persistence handler.

schemaHandler

protected StoreSchemaHandler schemaHandler

Schema handler.

connectionMgr

protected ConnectionManager connectionMgr

ConnectionManager

txConnectionFactoryName

protected java.lang.String txConnectionFactoryName

Name of transactional connection factory.

nontxConnectionFactoryName

protected java.lang.String nontxConnectionFactoryName

Name of non-transactional connection factory (null if not present).

Constructor Detail

AbstractStoreManager

protected AbstractStoreManager(java.lang.String key,
                               ClassLoaderResolver clr,
                               OMFContext omfContext)

Constructor for a new StoreManager. Stores the basic information required for the datastore management.

Parameters:

key - Key for this StoreManager

clr - the ClassLoaderResolver

omfContext - The corresponding ObjectManagerFactory context.

Method Detail

registerConnectionMgr

protected void registerConnectionMgr()

Register the default ConnectionManager implementation

registerConnectionFactory

protected void registerConnectionFactory()

Register the Connection Factory defined in plugins

close

public void close()

Description copied from interface: StoreManager

Release of resources.

Specified by:

close in interface StoreManager

getConnectionManager

public ConnectionManager getConnectionManager()

Description copied from interface: StoreManager

Accessor for the connection manager for this store manager.

Specified by:

getConnectionManager in interface StoreManager

Returns:

connection manager

getConnection

public ManagedConnection getConnection(ExecutionContext ec)

Accessor for a connection for the specified ObjectManager.

If there is an active transaction, a connection from the transactional connection factory will be returned. If there is no active transaction, a connection from the nontransactional connection factory will be returned.

Specified by:

getConnection in interface StoreManager

Parameters:

ec - execution context

Returns:

The Connection

Throws:

NucleusException - Thrown if an error occurs getting the connection

getConnection

public ManagedConnection getConnection(ExecutionContext ec,
                                       java.util.Map options)

Accessor for a connection for the specified ObjectManager.

If there is an active transaction, a connection from the transactional connection factory will be returned. If there is no active transaction, a connection from the nontransactional connection factory will be returned.

Specified by:

getConnection in interface StoreManager

Parameters:

ec - execution context

options - connetion options

Returns:

The Connection

Throws:

NucleusException - Thrown if an error occurs getting the connection

getConnection

public ManagedConnection getConnection(int isolation_level)

Utility to return a non-transactional Connection. This returns a connection from a secondary DataSource (e.g. javax.jdo.option.connectionFactory2Name), if it is provided.

Parameters:

isolation_level - The transaction isolation scheme to use e.g Connection.TRANSACTION_NONE Pass in -1 if just want the default

Returns:

The Connection to the datastore

Throws:

NucleusException - if an error occurs getting the connection

getConnectionDriverName

public java.lang.String getConnectionDriverName()

Convenience accessor for the driver name to use for the connection (if applicable for this datastore).

Specified by:

getConnectionDriverName in interface StoreManager

Returns:

Driver name for the connection

getConnectionURL

public java.lang.String getConnectionURL()

Convenience accessor for the URL for the connection

Specified by:

getConnectionURL in interface StoreManager

Returns:

Connection URL

getConnectionUserName

public java.lang.String getConnectionUserName()

Convenience accessor for the username to use for the connection

Specified by:

getConnectionUserName in interface StoreManager

Returns:

Username

getConnectionPassword

public java.lang.String getConnectionPassword()

Convenience accessor for the password to use for the connection. Will perform decryption if the persistence property "datanucleus.ConnectionPasswordDecrypter" has also been specified.

Specified by:

getConnectionPassword in interface StoreManager

Returns:

Password

getConnectionFactory

public java.lang.Object getConnectionFactory()

Convenience accessor for the factory for the connection (transactional).

Specified by:

getConnectionFactory in interface StoreManager

Returns:

Connection Factory (transactional)

getConnectionFactoryName

public java.lang.String getConnectionFactoryName()

Convenience accessor for the factory name for the connection (transactional).

Specified by:

getConnectionFactoryName in interface StoreManager

Returns:

Connection Factory name (transactional)

getConnectionFactory2

public java.lang.Object getConnectionFactory2()

Convenience accessor for the factory for the connection (non-transactional).

Specified by:

getConnectionFactory2 in interface StoreManager

Returns:

Connection Factory (non-transactional)

getConnectionFactory2Name

public java.lang.String getConnectionFactory2Name()

Convenience accessor for the factory name for the connection (non-transactional).

Specified by:

getConnectionFactory2Name in interface StoreManager

Returns:

Connection Factory name (non-transactional)

getRuntimeManager

public StoreManagerRuntime getRuntimeManager()

Description copied from interface: StoreManager

Accessor for the runtime management of this component (if specified as required to the PMF/EMF).

Specified by:

getRuntimeManager in interface StoreManager

Returns:

Runtime manager (JMX) for this store

getPersistenceHandler

public StorePersistenceHandler getPersistenceHandler()

Description copied from interface: StoreManager

Accessor for the store persistence handler.

Specified by:

getPersistenceHandler in interface StoreManager

Returns:

Store persistence handler.

getSchemaHandler

public StoreSchemaHandler getSchemaHandler()

Description copied from interface: StoreManager

Accessor for the store schema handler (if this datastore supports the concept of a schema).

Specified by:

getSchemaHandler in interface StoreManager

Returns:

Store schema handler.

getNucleusSequence

public NucleusSequence getNucleusSequence(ExecutionContext ec,
                                          SequenceMetaData seqmd)

Method to return a datastore sequence for this datastore matching the passed sequence MetaData.

Specified by:

getNucleusSequence in interface StoreManager

Parameters:

ec - execution context

seqmd - SequenceMetaData

Returns:

The Sequence

getNucleusConnection

public NucleusConnection getNucleusConnection(ExecutionContext ec)

Description copied from interface: StoreManager

Method to return a connection for the ObjectManager.

Specified by:

getNucleusConnection in interface StoreManager

Parameters:

ec - execution context

Returns:

The datastore Connection

getValueGenerationManager

public ValueGenerationManager getValueGenerationManager()

Description copied from interface: StoreManager

Accessor for the ValueGenerationManager for obtaining sequences.

Specified by:

getValueGenerationManager in interface StoreManager

Returns:

The ValueGenerationManagerr for this datastore

getApiAdapter

public ApiAdapter getApiAdapter()

Description copied from interface: StoreManager

Accessor for the API adapter.

Specified by:

getApiAdapter in interface StoreManager

Returns:

API adapter

getStoreManagerKey

public java.lang.String getStoreManagerKey()

Description copied from interface: StoreManager

Accessor for the key for this store manager.

Specified by:

getStoreManagerKey in interface StoreManager

Returns:

StoreManager key

getQueryCacheKey

public java.lang.String getQueryCacheKey()

Description copied from interface: StoreManager

Accessor for the key used for representing this store manager in the query cache.

Specified by:

getQueryCacheKey in interface StoreManager

Returns:

Key for the query cache

getOMFContext

public OMFContext getOMFContext()

Description copied from interface: StoreManager

Accessor for the context in which this StoreManager is running

Specified by:

getOMFContext in interface StoreManager

Returns:

Returns the context.

getMetaDataManager

public MetaDataManager getMetaDataManager()

getDatastoreDate

public java.util.Date getDatastoreDate()

Description copied from interface: StoreManager

Get the date/time of the datastore.

Specified by:

getDatastoreDate in interface StoreManager

Returns:

Date/time of the datastore

registerStoreData

protected void registerStoreData(StoreData data)

Method to register some data with the store. This will also register the data with the starter process.

Parameters:

data - The StoreData to add

deregisterAllStoreData

protected void deregisterAllStoreData()

Method to deregister all existing store data so that we are managing nothing.

logConfiguration

protected void logConfiguration()

Convenience method to log the configuration of this store manager.

printInformation

public void printInformation(java.lang.String category,
                             java.io.PrintStream ps)
                      throws java.lang.Exception

Method to output the information about the StoreManager. Supports the category "DATASTORE".

Specified by:

printInformation in interface StoreManager

Parameters:

category - Category of information

ps - PrintStream

Throws:

java.lang.Exception - Thrown if an error occurs in the output process

initialiseAutoStart

protected void initialiseAutoStart(ClassLoaderResolver clr)
                            throws DatastoreInitialisationException

Method to initialise the auto-start mechanism, loading up the classes from its store into memory so that we start from where we got to last time. Utilises the "autoStartMechanism" field that should have been set before now.

Parameters:

clr - The ClassLoaderResolver

Throws:

DatastoreInitialisationException

clearAutoStarter

protected void clearAutoStarter()

Method to clear the Auto-Starter status.

managesClass

public boolean managesClass(java.lang.String className)

Description copied from interface: StoreManager

Accessor for whether the specified class is managed currently

Specified by:

managesClass in interface StoreManager

Parameters:

className - The name of the class

Returns:

Whether it is managed

addClass

public void addClass(java.lang.String className,
                     ClassLoaderResolver clr)

Description copied from interface: StoreManager

Method to add a class to the managed list for this datastore manager.

Specified by:

addClass in interface StoreManager

Parameters:

className - Name of the class

clr - The ClassLoaderResolver

addClasses

public void addClasses(java.lang.String[] classNames,
                       ClassLoaderResolver clr)

Description copied from interface: StoreManager

Add classes to the persistence model for the datastore.

This method is primarily useful for applications that wish to perform all of their datastore initialization up front, rather than wait for the runtime to do it on-demand.

Specified by:

addClasses in interface StoreManager

Parameters:

classNames - The class(es) to be added.

clr - The ClassLoaderResolver

newStoreData

protected StoreData newStoreData(ClassMetaData cmd,
                                 ClassLoaderResolver clr)

Instantiate a StoreData instance using the provided ClassMetaData and ClassLoaderResolver. Override this method if you want to instantiate a subclass of StoreData.

Parameters:

cmd - MetaData for the class

clr - ClassLoader resolver

removeAllClasses

public void removeAllClasses(ClassLoaderResolver clr)

Description copied from interface: StoreManager

Remove all classes from the persistence model for the datastore. This empties the datastore of all datastore objects managed by us. All objects of types not managed are left untouched. In the case of RDBMS this means drop all tables for types managed by us.

Specified by:

removeAllClasses in interface StoreManager

Parameters:

clr - The ClassLoaderResolver

manageClassForIdentity

public java.lang.String manageClassForIdentity(java.lang.Object id,
                                               ClassLoaderResolver clr)

Description copied from interface: StoreManager

Convenience method to ensure that the class defined by the passed OID/SingleFIeldIdentity is managed by the store.

Specified by:

manageClassForIdentity in interface StoreManager

Parameters:

id - OID

clr - ClassLoader resolver

Returns:

The class name of the class associated to this identity

getExtent

public Extent getExtent(ExecutionContext ec,
                        java.lang.Class c,
                        boolean subclasses)

Description copied from interface: StoreManager

Interface to getting an Extent for a class.

Specified by:

getExtent in interface StoreManager

Parameters:

ec - execution context

c - The class requiring the Extent

subclasses - Whether to include subclasses of 'c'

Returns:

The Extent.

supportsQueryLanguage

public boolean supportsQueryLanguage(java.lang.String language)

Description copied from interface: StoreManager

Accessor for whether this query language is supported.

Specified by:

supportsQueryLanguage in interface StoreManager

Parameters:

language - The language

Returns:

Whether it is supported.

supportsValueStrategy

public boolean supportsValueStrategy(java.lang.String strategy)

Accessor for whether this value strategy is supported.

Specified by:

supportsValueStrategy in interface StoreManager

Parameters:

strategy - The strategy

Returns:

Whether it is supported.

getClassNameForObjectID

public java.lang.String getClassNameForObjectID(java.lang.Object id,
                                                ClassLoaderResolver clr,
                                                ExecutionContext ec)

Description copied from interface: StoreManager

Returns the class corresponding to the given object identity. If the object is an OID (datastore-identity), return the PC class specified in the identity. If the object is SingleFieldIdentity, return the PC class specified in the identity If the object is an AppID PK, return the PC class that uses it. If the object is a SCOID, return the SCO class. If the object is a PersistenceCapable class, return the class.

Specified by:

getClassNameForObjectID in interface StoreManager

Parameters:

id - The identity of some object.

clr - ClassLoader resolver

ec - execution context

Returns:

For datastore identity, return the class of the corresponding object. For application identity, return the class of the corresponding object or null if object does not exist.

isStrategyDatastoreAttributed

public boolean isStrategyDatastoreAttributed(IdentityStrategy identityStrategy,
                                             boolean datastoreIdentityField)

Method to return if a particular value strategy is attributed by the datastore. In this implementation we return true for IDENTITY, and false for others. Override in subclass if the datastore will attribute e.g SEQUENCE in the datastore.

Specified by:

isStrategyDatastoreAttributed in interface StoreManager

Parameters:

identityStrategy - The strategy

datastoreIdentityField - Whether this is a datastore id field

Returns:

Whether the strategy is attributed in the datastore

getStrategyValue

public java.lang.Object getStrategyValue(ExecutionContext ec,
                                         AbstractClassMetaData cmd,
                                         int absoluteFieldNumber)

Description copied from interface: StoreManager

Method to retrieve the value for a strategy for a particular field.

Specified by:

getStrategyValue in interface StoreManager

Parameters:

ec - execution context

cmd - AbstractClassMetaData for the class

absoluteFieldNumber - The field number

Returns:

The value

getStrategyForNative

protected java.lang.String getStrategyForNative(AbstractClassMetaData cmd,
                                                int absFieldNumber)

Method defining which value-strategy to use when the user specifies "native". Returns "increment" no matter what the field is. Override if your datastore requires something else.

Parameters:

cmd - Class requiring the strategy

absFieldNumber - Field of the class

Returns:

Just returns "increment".

getStrategyValueForGenerator

protected java.lang.Object getStrategyValueForGenerator(ValueGenerator generator,
                                                        ExecutionContext ec)

Accessor for the next value from the specified generator. This implementation simply returns generator.next(). Any case where the generator requires datastore connections should override this method.

Parameters:

generator - The generator

ec - execution context

Returns:

The next value.

getPropertiesForGenerator

protected java.util.Properties getPropertiesForGenerator(AbstractClassMetaData cmd,
                                                         int absoluteFieldNumber,
                                                         ExecutionContext ec,
                                                         SequenceMetaData seqmd,
                                                         TableGeneratorMetaData tablegenmd)

Method to return the properties to pass to the generator for the specified field.

Parameters:

cmd - MetaData for the class

absoluteFieldNumber - Number of the field (-1 = datastore identity)

ec - execution context

seqmd - Any sequence metadata

tablegenmd - Any table generator metadata

Returns:

The properties to use for this field

performVersionCheck

public void performVersionCheck(ObjectProvider sm,
                                java.lang.Object versionDatastore,
                                VersionMetaData versionMetaData)

Description copied from interface: StoreManager

Perform an optimistic version check on the passed object, against the passed version in the datastore.

Specified by:

performVersionCheck in interface StoreManager

Parameters:

sm - StateManager of the object to check

versionDatastore - Version of the object in the datastore

versionMetaData - VersionMetaData to use for checking

getSubClassesForClass

public java.util.HashSet<java.lang.String> getSubClassesForClass(java.lang.String className,
                                                                 boolean includeDescendents,
                                                                 ClassLoaderResolver clr)

Description copied from interface: StoreManager

Utility to return the names of the classes that are known subclasses of the provided class. Actually uses the MetaDataManager for determining what is a subclass since the MetaData is often registered before being needed by the Store.

Specified by:

getSubClassesForClass in interface StoreManager

Parameters:

className - Class for which we search for subclasses.

includeDescendents - Whether to include subclasses of subclasses etc

clr - The ClassLoaderResolver

Returns:

Set of classes that are subclasses of the input class. TODO Use method in MetaDataManager and remove this

notifyObjectIsOutdated

public void notifyObjectIsOutdated(ObjectProvider sm)

Description copied from interface: StoreManager

Notifies this store manager that the main memory (RAM, heap) copy of the PC object of the supplied StateManager may not be regarded as valid anymore. (The most common case is that the state of the PC becomes HOLLOW). This is especially important for object databases employing implicit storing from the main memory to the database (like DB4O). These databases may stop tracking the main memory copy and linking it with its on-disk copy, thus releasing memory. More importantly, these databases then know that the object should be reloaded when it is (maybe even implicitly) accessed again. To be clear: There may be multiple copies of the data of one PC object (from the user perspective), namely a copy in main memory (on the Java heap) and a copy in the database (usually on disk). As there may be multiple copies, some of these copies may be outdated or invalid. In case such a copy is to be accessed, its contents should not be used. Rather than that, the outdated copy should be overwritten by an authorative copy. This method marks the main memory copy of the object (on the Java heap) to be outdated in that sense.

Specified by:

notifyObjectIsOutdated in interface StoreManager

getBackingStoreForField

public Store getBackingStoreForField(ClassLoaderResolver clr,
                                     AbstractMemberMetaData fmd,
                                     java.lang.Class type)

Description copied from interface: StoreManager

Accessor for the backing store for the specified field. Override it if the store needs this

Specified by:

getBackingStoreForField in interface StoreManager

Parameters:

clr - ClassLoader resolver

fmd - MetaData for the field/property

type - Type

Returns:

Backing store

getSupportedOptions

public java.util.Collection<java.lang.String> getSupportedOptions()

Accessor for the supported options in string form. Typical values specified here are :-

• ApplicationIdentity - if the datastore supports application identity
• DatastoreIdentity - if the datastore supports datastore identity
• OptimisticTransaction - if the datastore supports optimistic locking
• BackedSCO - if the datastore requires SCO wrappers that have a backing store
• ORM - if the datastore supports (some) ORM concepts
• TransactionIsolationLevel.read-committed - if supporting this txn isolation level
• TransactionIsolationLevel.read-uncommitted - if supporting this txn isolation level
• TransactionIsolationLevel.repeatable-read - if supporting this txn isolation level
• TransactionIsolationLevel.serializable - if supporting this txn isolation level
• TransactionIsolationLevel.snapshot - if supporting this txn isolation level
• Query.Cancel - if supporting cancelling of queries
• Query.Timeout - if supporting timeout of queries

Specified by:

getSupportedOptions in interface StoreManager

assertReadOnlyForUpdateOfObject

public void assertReadOnlyForUpdateOfObject(ObjectProvider op)

Convenience method to assert when this StoreManager is read-only and the specified object is attempting to be updated.

Parameters:

op - ObjectProvider for the object

transactionStarted

public void transactionStarted(ExecutionContext ec)

Description copied from interface: StoreManager

Method to inform the StoreManager that a transaction has started for the specified execution context. This allows the StoreManager to initialise any objects as required.

Specified by:

transactionStarted in interface StoreManager

Parameters:

ec - ExecutionContext

transactionCommitted

public void transactionCommitted(ExecutionContext ec)

Description copied from interface: StoreManager

Method to inform the StoreManager that a transaction has committed for the specified execution context. This allows the StoreManager to close any objects as required.

Specified by:

transactionCommitted in interface StoreManager

Parameters:

ec - ExecutionContext

transactionRolledBack

public void transactionRolledBack(ExecutionContext ec)

Description copied from interface: StoreManager

Method to inform the StoreManager that a transaction has rolled back for the specified execution context. This allows the StoreManager to close any objects as required.

Specified by:

transactionRolledBack in interface StoreManager

Parameters:

ec - ExecutionContext