com.metamatrix.common.buffer
Interface BufferManager

All Known Implementing Classes:

BufferManagerImpl

public interface BufferManager

The buffer manager controls how memory is used and how data flows through the system. It uses storage managers to retrieve data, store data, and transfer data. The buffer manager has algorithms that tell it when and how to store data. The buffer manager should also be aware of memory management issues.

Nested Class Summary

static class	BufferManager.TupleSourceStatus
static class	BufferManager.TupleSourceType

Method Summary

void	addStorageManager(StorageManager storageManager) Adds a StorageManager to this BufferManager instance.
void	addStreamablePart(TupleSourceID tupleSourceID, LobChunk streamGlob, int beginRow) Add a streamable object to the persistent store.
void	addTupleBatch(TupleSourceID tupleSourceID, TupleBatch tupleBatch) Adds a batch of tuples for the specified tuple source
TupleSourceID	createTupleSource(java.util.List elements, java.lang.String[] types, java.lang.String groupName, BufferManager.TupleSourceType tupleSourceType) Creates a tuple source based on a schema and properties describing hints about the source
int	getConnectorBatchSize() Get the batch size to use when reading data from a connector.
int	getFinalRowCount(TupleSourceID tupleSourceID) Gets the final row count if tuple source is FULL, otherwise returns -1.
int	getProcessorBatchSize() Get the batch size to use during query processing.
int	getRowCount(TupleSourceID tupleSourceID) Gets the current row count
BufferManager.TupleSourceStatus	getStatus(TupleSourceID tupleSourceID) Gets the status of the tuple source
LobChunk	getStreamablePart(TupleSourceID tupleSourceID, int beginRow) Returns the streamable batch object's part stored with specified identifier
java.util.List	getTupleSchema(TupleSourceID tupleSourceID) Gets a tuple source schema by ID
IndexedTupleSource	getTupleSource(TupleSourceID tupleSourceID) Gets a tuple source by ID
void	initialize(java.lang.String location, java.util.Properties properties) Prompts this implementation to initialize itself with the supplied Properties.
TupleBatch	pinTupleBatch(TupleSourceID tupleSourceID, int beginRow, int maxEndRow) Gets a tuple batch by ID and indexes.
void	releasePinnedBatches() Release batches that have been pinned by this thread.
void	removeTupleSource(TupleSourceID tupleSourceID) Removes a tuple source by ID
void	removeTupleSources(java.lang.String groupName) Removes all tuple sources by group name
void	setStatus(TupleSourceID tupleSourceID, BufferManager.TupleSourceStatus status) Sets the status of the tuple source
void	stop()
void	unpinTupleBatch(TupleSourceID tupleSourceID, int firstRow, int lastRow) Unpins a range of rows from the given tuple source

Method Detail

initialize

void initialize(java.lang.String location,
                java.util.Properties properties)
                throws MetaMatrixComponentException

Prompts this implementation to initialize itself with the supplied Properties. The implementation Class should document what properties are necessary, if any.

Parameters:

lookup - Class used to determine identity and lookup other managers

properties - Properties required to initialize the Buffer Manager

Throws:

BufferException - if there was a problem initializing

MetaMatrixComponentException

getProcessorBatchSize

int getProcessorBatchSize()

Get the batch size to use during query processing.

Returns:

Batch size (# of rows)

getConnectorBatchSize

int getConnectorBatchSize()

Get the batch size to use when reading data from a connector.

Returns:

Batch size (# of rows)

addStorageManager

void addStorageManager(StorageManager storageManager)

Adds a StorageManager to this BufferManager instance. This method may be called multiple times; it will be first called after the call to initialize(java.lang.String, java.util.Properties).

Parameters:

storageManager - Storage manager to add

createTupleSource

TupleSourceID createTupleSource(java.util.List elements,
                                java.lang.String[] types,
                                java.lang.String groupName,
                                BufferManager.TupleSourceType tupleSourceType)
                                throws MetaMatrixComponentException

Creates a tuple source based on a schema and properties describing hints about the source

Parameters:

elements - Elements of the tuple source

groupName - Tuple source group name

tupleSourceType - Type of tuple source

Returns:

Identifier for tuple source

Throws:

MetaMatrixComponentException - indicating a non-business-related exception (such as a communication exception)

removeTupleSource

void removeTupleSource(TupleSourceID tupleSourceID)
                       throws TupleSourceNotFoundException,
                              MetaMatrixComponentException

Removes a tuple source by ID

Parameters:

tupleSourceID - Tuple source identifier

Throws:

TupleSourceNotFoundException - if tuple source could not be found

MetaMatrixComponentException - indicating a non-business-related exception (such as a communication exception)

removeTupleSources

void removeTupleSources(java.lang.String groupName)
                        throws MetaMatrixComponentException

Removes all tuple sources by group name

Parameters:

groupName - Tuple source group name

Throws:

TupleSourceNotFoundException - if tuple source could not be found

MetaMatrixComponentException - indicating a non-business-related exception (such as a communication exception)

getTupleSource

IndexedTupleSource getTupleSource(TupleSourceID tupleSourceID)
                                  throws TupleSourceNotFoundException,
                                         MetaMatrixComponentException

Gets a tuple source by ID

Parameters:

tupleSourceID - Tuple source identifier

Returns:

Tuple source to get tuples from the specified source

Throws:

TupleSourceNotFoundException - if tuple source could not be found

MetaMatrixComponentException - indicating a non-business-related exception (such as a communication exception)

pinTupleBatch

TupleBatch pinTupleBatch(TupleSourceID tupleSourceID,
                         int beginRow,
                         int maxEndRow)
                         throws TupleSourceNotFoundException,
                                MemoryNotAvailableException,
                                MetaMatrixComponentException

Gets a tuple batch by ID and indexes. Pins this tuple batch in memory until it is unpinned or tuple source is removed. If memory does not exist to pin the batch, a MemoryNotAvailableException is thrown.

Parameters:

tupleSourceID - Tuple source identifier

beginRow - First row index to return

maxEndRow - Maximum last row index to return, may be less actually returned

Returns:

Batch of rows starting from beginRow and not past maxEndRow

Throws:

TupleSourceNotFoundException - if tuple source could not be found

MetaMatrixComponentException - indicating a non-business-related exception (such as a communication exception)

MemoryNotAvailableException - If memory was not available for the pin

unpinTupleBatch

void unpinTupleBatch(TupleSourceID tupleSourceID,
                     int firstRow,
                     int lastRow)
                     throws TupleSourceNotFoundException,
                            MetaMatrixComponentException

Unpins a range of rows from the given tuple source

Parameters:

tupleSourceID - Tuple source identifier

firstRow - First row to unpin

lastRow - Last row to unpin (inclusive)

Throws:

TupleSourceNotFoundException - if tuple source could not be found

MetaMatrixComponentException - indicating a non-business-related exception (such as a communication exception)

getTupleSchema

java.util.List getTupleSchema(TupleSourceID tupleSourceID)
                              throws TupleSourceNotFoundException,
                                     MetaMatrixComponentException

Gets a tuple source schema by ID

Parameters:

tupleSourceID - Tuple source identifier

Returns:

List of ElementSymbol describing elements of tuple source

Throws:

TupleSourceNotFoundException - if tuple source could not be found

MetaMatrixComponentException - indicating a non-business-related exception (such as a communication exception)

addTupleBatch

void addTupleBatch(TupleSourceID tupleSourceID,
                   TupleBatch tupleBatch)
                   throws TupleSourceNotFoundException,
                          MetaMatrixComponentException

Adds a batch of tuples for the specified tuple source

Parameters:

tupleSourceID - Tuple source identifier

tupleBatch - Batch of rows to add

Throws:

TupleSourceNotFoundException - if tuple source could not be found

MetaMatrixComponentException - indicating a non-business-related exception (such as a communication exception)

getRowCount

int getRowCount(TupleSourceID tupleSourceID)
                throws TupleSourceNotFoundException,
                       MetaMatrixComponentException

Gets the current row count

Parameters:

tupleSourceID - Tuple source identifier

Returns:

Current known number of rows in tuple source

Throws:

TupleSourceNotFoundException - if tuple source could not be found

MetaMatrixComponentException - indicating a non-business-related exception (such as a communication exception)

setStatus

void setStatus(TupleSourceID tupleSourceID,
               BufferManager.TupleSourceStatus status)
               throws TupleSourceNotFoundException,
                      MetaMatrixComponentException

Sets the status of the tuple source

Parameters:

tupleSourceID - Tuple source identifier

status - New status

Throws:

TupleSourceNotFoundException - if tuple source could not be found

MetaMatrixComponentException - indicating a non-business-related exception (such as a communication exception)

See Also:

BufferManager.TupleSourceStatus.ACTIVE, BufferManager.TupleSourceStatus.FULL

getStatus

BufferManager.TupleSourceStatus getStatus(TupleSourceID tupleSourceID)
                                          throws TupleSourceNotFoundException,
                                                 MetaMatrixComponentException

Gets the status of the tuple source

Parameters:

tupleSourceID - Tuple source identifier

Returns:

Status of tuple source

Throws:

TupleSourceNotFoundException - if tuple source could not be found

MetaMatrixComponentException - indicating a non-business-related exception (such as a communication exception)

See Also:

BufferManager.TupleSourceStatus.ACTIVE, BufferManager.TupleSourceStatus.FULL

getFinalRowCount

int getFinalRowCount(TupleSourceID tupleSourceID)
                     throws TupleSourceNotFoundException,
                            MetaMatrixComponentException

Gets the final row count if tuple source is FULL, otherwise returns -1.

Parameters:

tupleSourceID - Tuple source identifier

Returns:

Final row count if status == FULL, -1 otherwise

Throws:

TupleSourceNotFoundException

MetaMatrixComponentException

addStreamablePart

void addStreamablePart(TupleSourceID tupleSourceID,
                       LobChunk streamGlob,
                       int beginRow)
                       throws TupleSourceNotFoundException,
                              MetaMatrixComponentException

Add a streamable object to the persistent store. The distinction is made between regular tuple sources and streamable object beacuse, streamable objects are fairly large in size can not be loaded totally into memory, as other tuple sources are done this mechanism allows to stream these objects chunk by chunk.

Parameters:

tupleSourceID -

streamGlob - part of the stream

stream -

Throws:

TupleSourceNotFoundException

MetaMatrixComponentException

getStreamablePart

LobChunk getStreamablePart(TupleSourceID tupleSourceID,
                           int beginRow)
                           throws TupleSourceNotFoundException,
                                  MetaMatrixComponentException

Returns the streamable batch object's part stored with specified identifier

Parameters:

tupleSourceID - - identifier

Returns:

LobChunk a part of the Streamable object stored.

Throws:

TupleSourceNotFoundException

MetaMatrixComponentException

stop

void stop()

releasePinnedBatches

void releasePinnedBatches()
                          throws MetaMatrixComponentException

Release batches that have been pinned by this thread. This method should be called when processing is terminated to ensure that the memory can be freed.

Throws:

MetaMatrixComponentException