Module org.apache.jena.tdb

Package org.apache.jena.tdb1.transaction

Class BlockMgrJournal

java.lang.Object

org.apache.jena.tdb1.transaction.BlockMgrJournal

All Implemented Interfaces:

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

public class BlockMgrJournal
extends Object
implements BlockMgr, TransactionLifecycle

Block manager that keeps temporary copies of updated blocks, then writes them to a journal when commitPrepare happens. No work is done in commitEnact because the TransactionManager is responsible to writing the blocks to the main storage.

Constructor Summary

Constructors

Constructor	Description
BlockMgrJournal(Transaction txn, FileRef fileRef, BlockMgr underlyingBlockMgr)

Method Summary

Modifier and Type	Method	Description
void	abort(Transaction txn)	End of active phase - will not be making these changes.
Block	allocate(int blockSize)	Allocate an uninitialized block - writable - call only inside a update sequence.
void	begin(Transaction txn)	Start an update transaction
void	beginIterator(Iterator<?> iterator)	Start of iterator
void	beginRead()	Start of read
void	beginUpdate()	Start of update
void	clearupCommitted(Transaction txn)	All done - transaction committed and incorporated in the base dataset - can now tidy up - called during journal flush if commiting.
void	close()	Close the block manager
void	commitPrepare(Transaction txn)	Prepare to commit; end of active phase.
void	committed(Transaction txn)	The commit has happened
void	enactCommitted(Transaction txn)	Update the base data - called during journal flush.
void	endIterator(Iterator<?> iterator)	Completion of iterator
void	endRead()	Completion of read
void	endUpdate()	Completion of update
void	free(Block block)	Announce a block is no longer in use (i.e it's now freed)
String	getLabel()
Block	getRead(long id)	Fetch a block, use for read only
Block	getReadIterator(long id)	Fetch a block, use for read only in an iterator
Block	getWrite(long id)	Fetch a block, use for write and read - only inside "update"
boolean	isClosed()	Is this block manager still usable?
boolean	isEmpty()	Answer whether there are any blocks in the collection being managed
void	overwrite(Block block)	Replace the contents of a block slot with new contents.
Block	promote(Block block)	Promote to writeable : it's OK to promote an already writeable block
void	release(Block block)	Release a block, unmodified.
void	sync()	Sync the block manager
void	syncForce()	Sync the block manager : system operation to ensure sync() is passed down
String	toString()
boolean	valid(int id)	Is this a valid block id?
void	write(Block block)	Write a block back - it still needs releasing.

Methods inherited from class java.lang.Object

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

Constructor Details

BlockMgrJournal

public BlockMgrJournal(Transaction txn,
 FileRef fileRef,
 BlockMgr underlyingBlockMgr)

Method Details

begin

public void begin(Transaction txn)

Description copied from interface: TransactionLifecycle

Start an update transaction

Specified by:

begin in interface TransactionLifecycle

commitPrepare

public void commitPrepare(Transaction txn)

Description copied from interface: TransactionLifecycle

Prepare to commit; end of active phase. Make changes safe; do not update the base data.

Specified by:

commitPrepare in interface TransactionLifecycle

committed

public void committed(Transaction txn)

Description copied from interface: TransactionLifecycle

The commit has happened

Specified by:

committed in interface TransactionLifecycle

enactCommitted

public void enactCommitted(Transaction txn)

Description copied from interface: TransactionLifecycle

Update the base data - called during journal flush.

Specified by:

enactCommitted in interface TransactionLifecycle

clearupCommitted

public void clearupCommitted(Transaction txn)

Description copied from interface: TransactionLifecycle

All done - transaction committed and incorporated in the base dataset - can now tidy up - called during journal flush if commiting.

Specified by:

clearupCommitted in interface TransactionLifecycle

abort

public void abort(Transaction txn)

Description copied from interface: TransactionLifecycle

End of active phase - will not be making these changes.

Specified by:

abort in interface TransactionLifecycle

allocate

public Block allocate(int blockSize)

Description copied from interface: BlockMgr

Allocate an uninitialized block - writable - call only inside a update sequence. If blockSize is -1, means "default/fixed size" for this BlockMgr

Specified by:

allocate in interface BlockMgr

getRead

public Block getRead(long id)

Description copied from interface: BlockMgr

Fetch a block, use for read only

Specified by:

getRead in interface BlockMgr

getReadIterator

public Block getReadIterator(long id)

Description copied from interface: BlockMgr

Fetch a block, use for read only in an iterator

Specified by:

getReadIterator in interface BlockMgr

getWrite

public Block getWrite(long id)

Description copied from interface: BlockMgr

Fetch a block, use for write and read - only inside "update"

Specified by:

getWrite in interface BlockMgr

promote

public Block promote(Block block)

Description copied from interface: BlockMgr

Promote to writeable : it's OK to promote an already writeable block

Specified by:

promote in interface BlockMgr

release

public void release(Block block)

Description copied from interface: BlockMgr

Release a block, unmodified.

Specified by:

release in interface BlockMgr

write

public void write(Block block)

Description copied from interface: BlockMgr

Write a block back - it still needs releasing.

Specified by:

write in interface BlockMgr

overwrite

public void overwrite(Block block)

Description copied from interface: BlockMgr

Replace the contents of a block slot with new contents. Block does not need releasing. The write() operation may not do real work if the block is mapped - this operation really does replace the contents with the new contents.

Specified by:

overwrite in interface BlockMgr

free

public void free(Block block)

Description copied from interface: BlockMgr

Announce a block is no longer in use (i.e it's now freed)

Specified by:

free in interface BlockMgr

isEmpty

public boolean isEmpty()

Description copied from interface: BlockMgr

Answer whether there are any blocks in the collection being managed

Specified by:

isEmpty in interface BlockMgr

valid

public boolean valid(int id)

Description copied from interface: BlockMgr

Is this a valid block id? (may be a free block)

Specified by:

valid in interface BlockMgr

close

public void close()

Description copied from interface: BlockMgr

Close the block manager

Specified by:

close in interface BlockMgr

Specified by:

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

isClosed

public boolean isClosed()

Description copied from interface: BlockMgr

Is this block manager still usable? Closed block managers can not perform any operations except this one.

Specified by:

isClosed in interface BlockMgr

sync

public void sync()

Description copied from interface: BlockMgr

Sync the block manager

Specified by:

sync in interface BlockMgr

Specified by:

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

syncForce

public void syncForce()

Description copied from interface: BlockMgr

Sync the block manager : system operation to ensure sync() is passed down

Specified by:

syncForce in interface BlockMgr

beginUpdate

public void beginUpdate()

Description copied from interface: BlockMgr

Start of update

Specified by:

beginUpdate in interface BlockMgr

endUpdate

public void endUpdate()

Description copied from interface: BlockMgr

Completion of update

Specified by:

endUpdate in interface BlockMgr

beginRead

public void beginRead()

Description copied from interface: BlockMgr

Start of read

Specified by:

beginRead in interface BlockMgr

endRead

public void endRead()

Description copied from interface: BlockMgr

Completion of read

Specified by:

endRead in interface BlockMgr

beginIterator

public void beginIterator(Iterator<?> iterator)

Description copied from interface: BlockMgr

Start of iterator

Specified by:

beginIterator in interface BlockMgr

endIterator

public void endIterator(Iterator<?> iterator)

Description copied from interface: BlockMgr

Completion of iterator

Specified by:

endIterator in interface BlockMgr

toString

public String toString()

Overrides:

toString in class Object

getLabel

public String getLabel()

Specified by:

getLabel in interface BlockMgr