com.solarmetric.kodo.runtime.datacache
Class DataCacheStoreManager

java.lang.Object
  |
  +--com.solarmetric.kodo.runtime.datacache.DataCacheStoreManager

All Implemented Interfaces:

StoreManager

public class DataCacheStoreManager

extends Object

implements StoreManager

StoreManager proxy that delegates to a data cache when possible.

Constructor Summary

DataCacheStoreManager(StoreManager sm, DataCache cache)
Constructor.

Method Summary

void	begin() Begin a data store transaction.
void	beginOptimistic() Notification that an optimistic transaction has started.
protected boolean	canCache(StateManagerImpl sm) Returns true if sm is eligible to be enlisted in the cache; otherwise returns false.
boolean	checkVersion(StateManagerImpl sm) Determine whether the given StateManager is the same version as the datastore version.
void	commit() Commit the current data store transaction.
Object	copyDataStoreId(Object oid, ClassMetaData meta) Copy the given object id value.
boolean	exists(Object oid, ClassMetaData meta) Verify that the given instance exists in the data store.
Collection	flush(Collection states) Flush the given state manager collection to the datastore, returning a collection of user exceptions encountered during flushing.
DataCache	getDataCache() Return the cache in use.
Class	getDataStoreIdClass(ClassMetaData meta) Return the class used by this StoreManager for datastore identity values.
StoreManager	getStoreManager() Return the internal store manager.
boolean	initialize(StateManagerImpl sm, com.solarmetric.kodo.runtime.JDOState state, Object conn) Initialize the given StateManager.
void	load(StateManagerImpl sm, Object conn, BitSet fields, boolean setVersion) Load the given StateManager.
Object	newDataStoreId(ClassMetaData meta) Create a new unique datastore identity for the given type.
Object	newDataStoreId(String str, ClassMetaData meta) Create a new unique datastore identity for the given type from the given string.
Extent	newExtent(ClassMetaData meta, boolean subclasses) Return an extent of the given candidate class, optionally including subclasses.
com.solarmetric.kodo.query.FilterExtensions	newFilterExtensions() Return a FilterExtensions implementation for use in queries.
protected com.solarmetric.kodo.runtime.PCData	newPCData(StateManagerImpl sm)
Query	newQuery(String language, Object template) Return a query implementation suitable for this runtime.
void	rollback() Rollback the current data store transaction.
void	setPersistenceManager(PersistenceManagerImpl pm) Set a reference to the corresponding PersistenceManager.

Methods inherited from class java.lang.Object

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

Constructor Detail

DataCacheStoreManager

public DataCacheStoreManager(StoreManager sm,
                             DataCache cache)

Constructor.

Parameters:

sm - the store manager to delegate to

cache - the cache to access for shared objects

Method Detail

getStoreManager

public StoreManager getStoreManager()

Return the internal store manager.

getDataCache

public DataCache getDataCache()

Return the cache in use.

setPersistenceManager

public void setPersistenceManager(PersistenceManagerImpl pm)

Description copied from interface: StoreManager

Set a reference to the corresponding PersistenceManager. This method will be called before the StoreManager is used.

Specified by:

setPersistenceManager in interface StoreManager

beginOptimistic

public void beginOptimistic()

Description copied from interface: StoreManager

Notification that an optimistic transaction has started. This method does not replace the StoreManager.begin() method, which will still be called when a true data store transaction should begin.

Specified by:

beginOptimistic in interface StoreManager

begin

public void begin()

Description copied from interface: StoreManager

Begin a data store transaction. If optimistic transactions are in use, this method will only be called when the user is ready to commit the transaction. At this time, the PersistenceManager will call this begin method, will store all modified data, and will call the commit method in succession, minimizing the length of the actual data store transaction. In this case, it is possible that the optimistic transaction does not have the latest versions of all instances (i.e. another transaction has modified the same instances and committed since the optimistic transaction started). On commit, an exception must be thrown on any attempt to overwrite data for an instance with an older version.

Specified by:

begin in interface StoreManager

commit

public void commit()

Description copied from interface: StoreManager

Commit the current data store transaction.

Specified by:

commit in interface StoreManager

rollback

public void rollback()

Description copied from interface: StoreManager

Rollback the current data store transaction.

Specified by:

rollback in interface StoreManager

exists

public boolean exists(Object oid,
                      ClassMetaData meta)

Description copied from interface: StoreManager

Verify that the given instance exists in the data store.

Specified by:

exists in interface StoreManager

checkVersion

public boolean checkVersion(StateManagerImpl sm)

Description copied from interface: StoreManager

Determine whether the given StateManager is the same version as the datastore version.

Specified by:

checkVersion in interface StoreManager

Following copied from interface: com.solarmetric.kodo.runtime.StoreManager

Parameters:

sm - the instance to check

Returns:

true if the instance is up-to-date, false otherwise

initialize

public boolean initialize(StateManagerImpl sm,
                          com.solarmetric.kodo.runtime.JDOState state,
                          Object conn)

Description copied from interface: StoreManager

Initialize the given StateManager. The oid of the StateManager will be set, and the meta field of the StateManager will be set to the class of the instance to load, or possibly one of its superclasses. Initialization involves first calling the StateManagerImpl#setPersistenceCapable method with a new instance of the correct type constructed with the JDOImplHelper#newInstance(Class,StateManager,Object) method (this will reset the meta field of the StateManager if the actual type was a subclass), then possibly loading any fields if desired. The version information for the StateManager should also be set via the StateManagerImpl.setVersion(java.lang.Object) method. If this method is called during a data store transaction, the instance should be locked.

Specified by:

initialize in interface StoreManager

Following copied from interface: com.solarmetric.kodo.runtime.StoreManager

Parameters:

sm - the instance to initialize

state - the JDO state to pass through to the state manager's initialize method

connection - the current connection information, or null if not given to the calling method of the persistence manager

Returns:

true if the matching instance exists in the data store, false otherwise

load

public void load(StateManagerImpl sm,
                 Object conn,
                 BitSet fields,
                 boolean setVersion)

Description copied from interface: StoreManager

Load the given StateManager. Note that any collection or map types loaded into the StateManager will be proxied with the correct type; therefore the StoreManager does not have to load the same concrete collection/map types as the instance declares. However, array types must be consistent with the array type stored by the PersistenceCapable instance. If this method is called during a data store transaction, the instance should be locked.

Specified by:

load in interface StoreManager

Following copied from interface: com.solarmetric.kodo.runtime.StoreManager

Parameters:

sm - the instance to load

connection - the current connection information, or null if not given to the calling method of the persistence manager

fields - the fields to load; the field corrsponding to the metadata field at each set bit position should be loaded; additional fields can be loaded if desired; attempting to load an additional field that has been dirtied will cause the load to be ignored; this bit set should not be modified

setVersion - if true, the version information should also be loaded from the db and set in the instance via the StateManagerImpl.setVersion(java.lang.Object) method

flush

public Collection flush(Collection states)

Description copied from interface: StoreManager

Flush the given state manager collection to the datastore, returning a collection of user exceptions encountered during flushing. The given state collection may include states that do not require data store action, such as persistent-clean instances. For datastore updates and inserts, the dirty fields of each state should be flushed. Datastore version information should be updated during flush, and the state manager's version indicator updated through the StateManagerImpl.setNextVersion(java.lang.Object) method. The current version will roll over to this next version upon successful commit.

Specified by:

flush in interface StoreManager

getDataStoreIdClass

public Class getDataStoreIdClass(ClassMetaData meta)

Description copied from interface: StoreManager

Return the class used by this StoreManager for datastore identity values.

Specified by:

getDataStoreIdClass in interface StoreManager

copyDataStoreId

public Object copyDataStoreId(Object oid,
                              ClassMetaData meta)

Description copied from interface: StoreManager

Copy the given object id value.

Specified by:

copyDataStoreId in interface StoreManager

newDataStoreId

public Object newDataStoreId(ClassMetaData meta)

Description copied from interface: StoreManager

Create a new unique datastore identity for the given type.

Specified by:

newDataStoreId in interface StoreManager

newDataStoreId

public Object newDataStoreId(String str,
                             ClassMetaData meta)

Description copied from interface: StoreManager

Create a new unique datastore identity for the given type from the given string.

Specified by:

newDataStoreId in interface StoreManager

newExtent

public Extent newExtent(ClassMetaData meta,
                        boolean subclasses)

Description copied from interface: StoreManager

Return an extent of the given candidate class, optionally including subclasses. If the extent is iterated within a data store transaction, returned instances should be locked.

Specified by:

newExtent in interface StoreManager

newQuery

public Query newQuery(String language,
                      Object template)

Description copied from interface: StoreManager

Return a query implementation suitable for this runtime. If the query is iterated within a data store transaction, returned instances should be locked.

Specified by:

newQuery in interface StoreManager

Following copied from interface: com.solarmetric.kodo.runtime.StoreManager

Parameters:

the - query language; implementations are only required to support javax.jdo.query.JDOQL

a - template query instance also from this StoreManager; this instance may be null; if not null, the filter, variables, parameters, imports, and candidate class should be copied from the template to the returned Query instance

newFilterExtensions

public com.solarmetric.kodo.query.FilterExtensions newFilterExtensions()

Description copied from interface: StoreManager

Return a FilterExtensions implementation for use in queries. To return no extensions, do:
return FilterExtensions.DefaultExtensions.newExtensions ()

Specified by:

newFilterExtensions in interface StoreManager

newPCData

protected com.solarmetric.kodo.runtime.PCData newPCData(StateManagerImpl sm)

canCache

protected boolean canCache(StateManagerImpl sm)

Returns true if sm is eligible to be enlisted in the cache; otherwise returns false.