org.objectweb.cjdbc.controller.scheduler.raidb1
Class RAIDb1OptimisticTransactionLevelScheduler

java.lang.Object
  org.objectweb.cjdbc.controller.scheduler.AbstractScheduler
      org.objectweb.cjdbc.controller.scheduler.raidb1.RAIDb1OptimisticTransactionLevelScheduler

public class RAIDb1OptimisticTransactionLevelScheduler

extends AbstractScheduler

This scheduler provides transaction level scheduling for RAIDb-1 controllers. Each write takes a lock on the table it affects. All following writes are blocked until the transaction of the first write completes. This scheduler automatically detects simple deadlocks and rollbacks the transaction inducing the deadlock. Note that transitive deadlocks (involving more than 2 tables are not detected).

Version:

1.0

Author:

Emmanuel Cecchet

Field Summary

private int	requestId
private SchedulerDatabaseSchema	schedulerDatabaseSchema

Fields inherited from class org.objectweb.cjdbc.controller.scheduler.AbstractScheduler

logger, needSQLMacroHandling, parsingGranularity, raidbLevel

Constructor Summary

RAIDb1OptimisticTransactionLevelScheduler()
Creates a new Optimistic Transaction Level Scheduler

Method Summary

private void	acquireLockAndSetRequestId(AbstractWriteRequest request, TransactionExclusiveLock tableLock)
protected void	commitTransaction(int transactionId) Commit a transaction given its id.
java.lang.String	getInformation() Get information about the Request Scheduler
java.lang.String	getXmlInformation() Get information about the Request Scheduler in xml format
void	mergeDatabaseSchema(DatabaseSchema dbs) Merge the given DatabaseSchema with the current one.
void	notifyWriteCompleted(AbstractWriteRequest request) Notify the completion of a write statement.
void	readCompleted(SelectRequest request) Notify the completion of a read statement.
private void	releaseLocks(int transactionId) Release all locks we may own on tables.
protected void	rollbackTransaction(int transactionId) Rollback a transaction given its id.
void	scheduleNonSuspendedWriteRequest(AbstractWriteRequest request) Additionally to scheduling the request, this method replaces the SQL Date macros such as now() with the current date.
void	scheduleReadRequest(SelectRequest request) Additionally to scheduling the request, this method replaces the SQL Date macros such as now() with the current date.
void	setDatabaseSchema(DatabaseSchema dbs) Sets the DatabaseSchema of the current virtual database.

Methods inherited from class org.objectweb.cjdbc.controller.scheduler.AbstractScheduler

begin, beginCompleted, commit, commitCompleted, getParsingGranularity, getPendingWrites, getRAIDbLevel, handleSQLMacros, hasSQLMacros, resumeNewTransactions, resumeWrites, rollback, rollbackCompleted, scheduleReadRequest, scheduleWriteRequest, setParsingGranularity, setRAIDbLevel, suspendNewTransactionsForCheckpoint, suspendWrites, writeCompleted

Methods inherited from class java.lang.Object

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

Field Detail

requestId

private int requestId

schedulerDatabaseSchema

private SchedulerDatabaseSchema schedulerDatabaseSchema

Constructor Detail

RAIDb1OptimisticTransactionLevelScheduler

public RAIDb1OptimisticTransactionLevelScheduler()

Creates a new Optimistic Transaction Level Scheduler

Method Detail

setDatabaseSchema

public void setDatabaseSchema(DatabaseSchema dbs)

Sets the DatabaseSchema of the current virtual database. This is only needed by some schedulers that will have to define their own scheduler schema

Overrides:

setDatabaseSchema in class AbstractScheduler

Parameters:

dbs - a DatabaseSchema value

See Also:

SchedulerDatabaseSchema

mergeDatabaseSchema

public void mergeDatabaseSchema(DatabaseSchema dbs)

Merge the given DatabaseSchema with the current one.

Overrides:

mergeDatabaseSchema in class AbstractScheduler

Parameters:

dbs - a DatabaseSchema value

See Also:

SchedulerDatabaseSchema

scheduleReadRequest

public final void scheduleReadRequest(SelectRequest request)
                               throws java.sql.SQLException

Additionally to scheduling the request, this method replaces the SQL Date macros such as now() with the current date.

Specified by:

scheduleReadRequest in class AbstractScheduler

Parameters:

request - Select request to schedule (SQL macros are already handled if needed)

Throws:

java.sql.SQLException - if a timeout occurs

See Also:

AbstractScheduler.scheduleReadRequest(SelectRequest)

readCompleted

public final void readCompleted(SelectRequest request)

Description copied from class: AbstractScheduler

Notify the completion of a read statement.

Specified by:

readCompleted in class AbstractScheduler

Parameters:

request - the completed request

See Also:

AbstractScheduler.readCompleted(SelectRequest)

scheduleNonSuspendedWriteRequest

public void scheduleNonSuspendedWriteRequest(AbstractWriteRequest request)
                                      throws java.sql.SQLException,
                                             RollbackException

Additionally to scheduling the request, this method replaces the SQL Date macros such as now() with the current date.

Specified by:

scheduleNonSuspendedWriteRequest in class AbstractScheduler

Parameters:

request - Write request to schedule (SQL macros are already handled if needed)

Throws:

RollbackException - if the transaction must be rollbacked

java.sql.SQLException - if a timeout occurs

See Also:

AbstractScheduler.scheduleWriteRequest(AbstractWriteRequest)

acquireLockAndSetRequestId

private void acquireLockAndSetRequestId(AbstractWriteRequest request,
                                        TransactionExclusiveLock tableLock)
                                 throws java.sql.SQLException

Throws:

java.sql.SQLException

notifyWriteCompleted

public final void notifyWriteCompleted(AbstractWriteRequest request)

Description copied from class: AbstractScheduler

Notify the completion of a write statement. This method does not need to be synchronized, it is enforced by the caller.

Specified by:

notifyWriteCompleted in class AbstractScheduler

Parameters:

request - the completed request

See Also:

AbstractScheduler.notifyWriteCompleted(AbstractWriteRequest)

commitTransaction

protected final void commitTransaction(int transactionId)

Description copied from class: AbstractScheduler

Commit a transaction given its id.

Specified by:

commitTransaction in class AbstractScheduler

Parameters:

transactionId - the transaction id

See Also:

AbstractScheduler.commitTransaction(int)

rollbackTransaction

protected final void rollbackTransaction(int transactionId)

Description copied from class: AbstractScheduler

Rollback a transaction given its id.

Specified by:

rollbackTransaction in class AbstractScheduler

Parameters:

transactionId - the transaction id

See Also:

AbstractScheduler.rollbackTransaction(int)

releaseLocks

private final void releaseLocks(int transactionId)

Release all locks we may own on tables.

Parameters:

transactionId - id of the transaction that releases the locks

getInformation

public java.lang.String getInformation()

Description copied from class: AbstractScheduler

Get information about the Request Scheduler

Specified by:

getInformation in class AbstractScheduler

Returns:

String containing information

See Also:

AbstractScheduler.getInformation()

getXmlInformation

public java.lang.String getXmlInformation()

Description copied from class: AbstractScheduler

Get information about the Request Scheduler in xml format

Specified by:

getXmlInformation in class AbstractScheduler

Returns:

String containing information in xml

See Also:

AbstractScheduler.getXmlInformation()