com.j_spaces.core.sadapter

Interface IStorageAdapter

All Known Implementing Classes:

BlobStoreStorageAdapter, MemorySA, SynchronizationStorageAdapter, SyncHybridStorageAdapter

public interface IStorageAdapter

IStorageAdapter is an interface that should be implemented by the Storage adapter. The IStorageAdapter interface contains methods for storing and retrieving entries and notify templates and to provide storage services to the engine .

All IStorageAdapter methods ( except init ) gets StorageAdapterContext object as the first parameter, which holds the connection information to the storage-adapter.

Method Summary

Modifier and Type	Method and Description
void	addIndexes(String typeName, SpaceIndex[] indexes)
void	commit(ServerTransaction xtn, boolean anyUpdates) Performs commit to transaction- delete taken entries, commit new entries.
int	count(ITemplateHolder template, String[] subClasses) Returns the number of entries that match the template.
Class<?>	getDataClass()
Map<String,IEntryHolder>	getEntries(Context context, Object[] ids, String typeName, IEntryHolder[] templates) Gets a map of entries from the storage adapter
IEntryHolder	getEntry(Context context, Object uid, String classname, IEntryHolder template) Gets an entry object from the storage adapter.
SpaceSynchronizationEndpoint	getSynchronizationInterceptor()
void	initialize() Initializes the SA for work (first API called by engine) If initMode is WARM : SA is required to set its internal working tables and environment to the state recorded in its persistent storage, and verify that all the SA space-related data is in consistent state.
ISAdapterIterator	initialLoad(Context context, ITemplateHolder template)
void	insertEntry(Context context, IEntryHolder entryHolder, boolean origin, boolean shouldReplicate) Inserts a new entry to the SA storage.
void	introduceDataType(ITypeDesc typeDesc)
boolean	isReadOnly() If returns true - then the storage adapter is read-only and can't be written to.
ISAdapterIterator<IEntryHolder>	makeEntriesIter(ITemplateHolder template, long SCNFilter, long leaseFilter, IServerTypeDesc[] subClasses) Returns an iterator with entries that match the template, and the other parameters.
void	prepare(Context context, ServerTransaction xtn, ArrayList<IEntryHolder> pLocked, boolean singleParticipant, Map<String,Object> partialUpdatesAndInPlaceUpdatesInfo, boolean shouldReplicate) Performs prepare to transaction- write to SA all new entries under the xtn, mark taken entries under the xtn
void	removeEntry(Context context, IEntryHolder entryHolder, boolean origin, boolean fromLeaseExpiration, boolean shouldReplicate) Removes an entry from the SA storage.
void	rollback(ServerTransaction xtn, boolean anyUpdates) Performs rollback to transaction- rewrite taken entries, remove new entries.
void	shutDown() called by the engine after all connections have been closed.
boolean	supportsExternalDB()
boolean	supportsGetEntries() Denotes whether the implementing class has an implementation for
boolean	supportsPartialUpdate()
void	updateEntry(Context context, IEntryHolder updatedEntry, boolean updateRedoLog, boolean origin, boolean[] partialUpdateValuesIndicators) updates an entry.

Method Detail

initialize

void initialize()
         throws SAException

Initializes the SA for work (first API called by engine)

If initMode is WARM : SA is required to set its internal working tables and environment to the state recorded in its persistent storage, and verify that all the SA space-related data is in consistent state.

If initMode is COLD : SA is required to clean its internal state.

Throws:

SAException - - In case a SQL error occurred.

initialLoad

ISAdapterIterator initialLoad(Context context,
                              ITemplateHolder template)
                       throws SAException

Throws:

SAException

insertEntry

void insertEntry(Context context,
                 IEntryHolder entryHolder,
                 boolean origin,
                 boolean shouldReplicate)
          throws SAException

Inserts a new entry to the SA storage.

Parameters:

entryHolder - entry to insert

Throws:

SAException

updateEntry

void updateEntry(Context context,
                 IEntryHolder updatedEntry,
                 boolean updateRedoLog,
                 boolean origin,
                 boolean[] partialUpdateValuesIndicators)
          throws SAException

updates an entry.

Parameters:

updatedEntry - new content, same UID and class

Throws:

SAException

removeEntry

void removeEntry(Context context,
                 IEntryHolder entryHolder,
                 boolean origin,
                 boolean fromLeaseExpiration,
                 boolean shouldReplicate)
          throws SAException

Removes an entry from the SA storage.

Parameters:

entryHolder - entry to remove

Throws:

SAException

prepare

void prepare(Context context,
             ServerTransaction xtn,
             ArrayList<IEntryHolder> pLocked,
             boolean singleParticipant,
             Map<String,Object> partialUpdatesAndInPlaceUpdatesInfo,
             boolean shouldReplicate)
      throws SAException

Performs prepare to transaction- write to SA all new entries under the xtn, mark taken entries under the xtn

Parameters:

xtn - transaction to prepare

pLocked - a vector of all entries locked (written or taken) under the xtn

singleParticipant - - if true, a transactional SA needs to do all the transaction related operations in one DB transaction and the prepare is actually the commit (no other transaction related APIs will be called for this xtn)

Throws:

SAException

rollback

void rollback(ServerTransaction xtn,
              boolean anyUpdates)
       throws SAException

Performs rollback to transaction- rewrite taken entries, remove new entries.

Parameters:

xtn - transaction to roll-back

anyUpdates - true if any updates performed under tjis xtn

Throws:

SAException

getEntry

IEntryHolder getEntry(Context context,
                      Object uid,
                      String classname,
                      IEntryHolder template)
               throws SAException

Gets an entry object from the storage adapter.

Parameters:

uid - ID of the entry to get

classname - class of the entry to get

template - selection template,may be null, currently used by cacheload/cachestore in order to pass primery key fields when GS uid is not saved in an external DB

Returns:

IEntryHolder

Throws:

SAException

getEntries

Map<String,IEntryHolder> getEntries(Context context,
                                    Object[] ids,
                                    String typeName,
                                    IEntryHolder[] templates)
                             throws SAException

Gets a map of entries from the storage adapter

Parameters:

ids - the ids of the entries to get

typeName - type of the entries to get

templates - templates matching the ids of the entries to get

Returns:

A map between entries uid and the entry holder returning null from this method implies this operation is not supported by the underlying storage mechanism and other methods for obtaining these entries should be applied.

Throws:

SAException

makeEntriesIter

ISAdapterIterator<IEntryHolder> makeEntriesIter(ITemplateHolder template,
                                                long SCNFilter,
                                                long leaseFilter,
                                                IServerTypeDesc[] subClasses)
                                         throws SAException

Returns an iterator with entries that match the template, and the other parameters.

Parameters:

template - - the entries should match that template.

SCNFilter - - if != 0 gets only templates that are <= from SCNFilter.

leaseFilter - if != 0 gets only templates that have expiration_time >= leaseFilter.

subClasses - - array of sub classes of the template, the entries should belong to a subcalss.

Returns:

ISadapterIterator

Throws:

SAException

commit

void commit(ServerTransaction xtn,
            boolean anyUpdates)
     throws SAException

Performs commit to transaction- delete taken entries, commit new entries.

Parameters:

xtn - transaction to commit

anyUpdates - true if any updates performed under tjis xtn

Throws:

SAException

count

int count(ITemplateHolder template,
          String[] subClasses)
   throws SAException

Returns the number of entries that match the template.

Parameters:

template - - the entries should match the template.

subClasses - - subclassesof the template, the entries can be in one of them.

Returns:

int - number of entries that match the parameters.

Throws:

SAException

shutDown

void shutDown()
       throws SAException

called by the engine after all connections have been closed. if the ShotDownString property is set- the string is executed by the SA

Throws:

SAException

isReadOnly

boolean isReadOnly()

If returns true - then the storage adapter is read-only and can't be written to.

supportsExternalDB

boolean supportsExternalDB()

supportsPartialUpdate

boolean supportsPartialUpdate()

supportsGetEntries

boolean supportsGetEntries()

Denotes whether the implementing class has an implementation for

introduceDataType

void introduceDataType(ITypeDesc typeDesc)

getSynchronizationInterceptor

SpaceSynchronizationEndpoint getSynchronizationInterceptor()

getDataClass

Class<?> getDataClass()

addIndexes

void addIndexes(String typeName,
                SpaceIndex[] indexes)