com.sparsity.sparksee.gdb

Class Session

java.lang.Object

com.sparsity.sparksee.gdb.Session

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

public class Session
extends java.lang.Object
implements java.io.Closeable

Session class.

A Session is a stateful period of activity of a user with the Database.

All the manipulation of a Database must be enclosed into a Session. A Session can be initiated from a Database instance and allows for getting a Graph instance which represents the persistent graph (the graph database).

Also, temporary data is associated to the Session, thus when a Session is closed, all the temporary data associated to the Session is removed too. Objects or Values instances or even session attributes are an example of temporary data.

Moreover, a Session is exclusive for a thread, thus if it is shared among threads results may be fatal or unexpected.

Check out the 'Processing' and 'Transactions' sections in the SPARKSEE User Manual for details about how Sessions work and the use of transactions.

Author:

Sparsity Technologies http://www.sparsity-technologies.com

Method Summary

Modifier and Type	Method and Description
void	begin() Begins a transaction.
void	beginUpdate() Begins an update transaction.
void	close() Closes the Session instance.
void	commit() Commits a transaction.
Graph	getGraph() Gets the Graph instance.
long	getInMemoryPoolCapacity() Gets the capacity of the in-memory pool.
boolean	isClosed() Gets if Session instance has been closed or not.
Objects	newObjects() Creates a new Objects instance.
Query	newQuery(QueryLanguage lang) Creates a new Query.
long	preCommit() PreCommits a transaction.
void	rollback() Rollbacks a transaction.

Methods inherited from class java.lang.Object

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

Method Detail

rollback

public void rollback()

Rollbacks a transaction.

preCommit

public long preCommit()

PreCommits a transaction.

YOU SHOULD NOT USE THIS METHOD. This method exists for a specific service and it is used to force that the transaction is written in the recovery log even though it had not been committed yet (and may never be).

Returns:

The transaction id. This has to be used in RedoPrecommited in case of a recovery process.

begin

public void begin()

Begins a transaction.

beginUpdate

public void beginUpdate()

Begins an update transaction.

newQuery

public Query newQuery(QueryLanguage lang)

Creates a new Query.

Parameters:

lang - The query language to create the query for

isClosed

public boolean isClosed()

Gets if Session instance has been closed or not.

Returns:

TRUE if the Session instance has been closed, FALSE otherwise.

See Also:

close()

commit

public void commit()

Commits a transaction.

getGraph

public Graph getGraph()

Gets the Graph instance.

Returns:

The Graph instance.

close

public void close()

Closes the Session instance.

It must be called to ensure the integrity of all data.

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

newObjects

public Objects newObjects()

Creates a new Objects instance.

Returns:

The new Objects instance.

getInMemoryPoolCapacity

public long getInMemoryPoolCapacity()

Gets the capacity of the in-memory pool.

Returns:

Returns the capacity of the in-memory pool