net.sf.farrago.db
Class FarragoDbNullTxnMgr

java.lang.Object
  net.sf.farrago.db.FarragoDbNullTxnMgr

All Implemented Interfaces:

FarragoSessionTxnMgr

Direct Known Subclasses:

LucidDbTxnMgr

public class FarragoDbNullTxnMgr
extends Object
implements FarragoSessionTxnMgr

FarragoDbNullTxnMgr is a do-nothing implementation of FarragoSessionTxnMgr. It is useful as a base class because it has a default implementation for generating new transaction ID's and notifying listeners.

Version:

$Id: //open/dev/farrago/src/net/sf/farrago/db/FarragoDbNullTxnMgr.java#7 $

Author:

John V. Sichi

Nested Class Summary

private static class

FarragoDbNullTxnMgr.LongTxnId

Field Summary

private List<FarragoSessionTxnListener>	listeners
private AtomicLong	nextId

Constructor Summary

FarragoDbNullTxnMgr()

Method Summary

protected void	accessTable(FarragoSessionTxnId txnId, List<String> localTableName, TableAccessMap.Mode accessType) Called by accessTables for each table accessed.
private void	accessTablePrivate(FarragoSessionTxnId txnId, List<String> localTableName, TableAccessMap.Mode accessType)
void	accessTables(FarragoSessionTxnId txnId, TableAccessMap accessMap) Notifies transaction manager that a collection of tables is about to be accessed.
void	addListener(FarragoSessionTxnListener listener) Adds a listener for transaction events.
FarragoSessionTxnId	beginTxn(FarragoSession session) Begins a new transaction.
void	endTxn(FarragoSessionTxnId txnId, FarragoSessionTxnEnd endType) Notifies transaction manager that a transaction is ending.
void	removeListener(FarragoSessionTxnListener listener) Removes a listener for transaction events.

Methods inherited from class java.lang.Object

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

Field Detail

nextId

private final AtomicLong nextId

listeners

private final List<FarragoSessionTxnListener> listeners

Constructor Detail

FarragoDbNullTxnMgr

public FarragoDbNullTxnMgr()

Method Detail

addListener

public void addListener(FarragoSessionTxnListener listener)

Description copied from interface: FarragoSessionTxnMgr

Adds a listener for transaction events.

Specified by:

addListener in interface FarragoSessionTxnMgr

Parameters:

listener - new listener

removeListener

public void removeListener(FarragoSessionTxnListener listener)

Description copied from interface: FarragoSessionTxnMgr

Removes a listener for transaction events.

Specified by:

removeListener in interface FarragoSessionTxnMgr

Parameters:

listener - listener to remove

beginTxn

public FarragoSessionTxnId beginTxn(FarragoSession session)

Description copied from interface: FarragoSessionTxnMgr

Begins a new transaction.

Specified by:

beginTxn in interface FarragoSessionTxnMgr

Parameters:

session - session initiating the transaction

Returns:

transaction ID

accessTables

public void accessTables(FarragoSessionTxnId txnId,
                         TableAccessMap accessMap)

Description copied from interface: FarragoSessionTxnMgr

Notifies transaction manager that a collection of tables is about to be accessed.

Specified by:

accessTables in interface FarragoSessionTxnMgr

Parameters:

txnId - ID of accessing transaction

accessMap - information about planned table accesses

accessTablePrivate

private void accessTablePrivate(FarragoSessionTxnId txnId,
                                List<String> localTableName,
                                TableAccessMap.Mode accessType)

accessTable

protected void accessTable(FarragoSessionTxnId txnId,
                           List<String> localTableName,
                           TableAccessMap.Mode accessType)

Called by accessTables for each table accessed. Default implementation is to do nothing; subclasses override this to take real actions such as calling a lock manager.

Parameters:

txnId - ID of accessing transaction

localTableName - qualified name of table as it is known in the local catalog

accessType - type of table access

endTxn

public void endTxn(FarragoSessionTxnId txnId,
                   FarragoSessionTxnEnd endType)

Description copied from interface: FarragoSessionTxnMgr

Notifies transaction manager that a transaction is ending.

Specified by:

endTxn in interface FarragoSessionTxnMgr

Parameters:

txnId - ID of ending transaction

endType - how transaction is ending