org.apache.jena.dboe.transaction.txn

Class StateMgrBase

java.lang.Object

org.apache.jena.dboe.transaction.txn.StateMgrBase

All Implemented Interfaces:

org.apache.jena.atlas.lib.Closeable, org.apache.jena.atlas.lib.Sync

Direct Known Subclasses:

StateMgrData

public abstract class StateMgrBase
extends Object
implements org.apache.jena.atlas.lib.Sync, org.apache.jena.atlas.lib.Closeable

Helper class for the manage the persistent state of a transactional. The persistent state is assumed to be a fixed size, or at least of known maximum size. May not be suitable for all transactional component implementations.

Method Summary

Modifier and Type	Method and Description
void	close()
BufferChannel	getBufferChannel() Low level control - for example, used for cloning setup.
ByteBuffer	getState() Return the serialized state using the internal ByteBuffer Typically called by "prepare" for the bytes to write to the journal.
void	readState() The read process : get all bytes on disk, deserialize
void	setState(ByteBuffer buff) Set the in-memory state from a ByteBuffer, for example, from journal recovery.
void	sync()
void	writeState() The write process : serialize, write, sync, After this, the bytes definitely are on disk, not in some OS cache

Methods inherited from class java.lang.Object

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

Method Detail

getBufferChannel

public BufferChannel getBufferChannel()

Low level control - for example, used for cloning setup. Use with care.

getState

public ByteBuffer getState()

Return the serialized state using the internal ByteBuffer Typically called by "prepare" for the bytes to write to the journal. Calls serialize(java.nio.ByteBuffer). This method does not perform an external I/O.

setState

public void setState(ByteBuffer buff)

Set the in-memory state from a ByteBuffer, for example, from journal recovery. This method does not perform an external I/O. Call "writeState" to put the n-memory state as the disk state.

writeState

public void writeState()

The write process : serialize, write, sync, After this, the bytes definitely are on disk, not in some OS cache

readState

public void readState()

The read process : get all bytes on disk, deserialize

sync

public void sync()

Specified by:

sync in interface org.apache.jena.atlas.lib.Sync

close

public void close()

Specified by:

close in interface org.apache.jena.atlas.lib.Closeable