org.alfresco.repo.domain.control

Interface ControlDAO

All Known Implementing Classes:

AbstractControlDAOImpl, ControlDAOImpl, ControlDAOImpl.PostgreSQL

public interface ControlDAO

DAO services for database control statements. It is sometimes necessary to issue control statements on a database connection; these are not usually supported in the ANSI SQL standard.

Since:

3.2SP1

Author:

Derek Hulley

Method Summary

Modifier and Type	Method and Description
Savepoint	createSavepoint(String savepoint) Create a "Save Point" in the current transaction, for later selective rollback.
void	executeBatch() Execute statements that were queued for batching.
void	releaseSavepoint(Savepoint savepoint) Remove a previously-created "Save Point", writing any intervening updates into the current transaction.
void	rollbackToSavepoint(Savepoint savepoint) Roll back to a previously-created "Save Point", discarding any intervening changes to the current transaction.
int	setTransactionIsolationLevel(int isolationLevel) Change the current transaction isolation level.
void	startBatch() Begin batching prepared statements for later execution.

Method Detail

startBatch

void startBatch()

Begin batching prepared statements for later execution.

See Also:

executeBatch()

executeBatch

void executeBatch()

Execute statements that were queued for batching.

See Also:

startBatch()

createSavepoint

Savepoint createSavepoint(String savepoint)

Create a "Save Point" in the current transaction, for later selective rollback. Creation must be accompanied by a matching rollbackToSavepoint(Savepoint) or releaseSavepoint(Savepoint).

  Savepoint savepoint = controlDAO.createSavepoint("functionF");
  try
  {
      // Do something that could fail e.g. blind insert that might violate unique constraints
      ...
      // Success, so remove savepoint or risk crashing on long-running transactions
      controlDAO.releaseSavepoint(savepoint);
  }
  catch (Throwable e)
  {
      controlDAO.rollbackToSavepoint(savepoint);
      // Throw something that client code might be able to react to or try something else
      ...
  }
 

Parameters:

savepoint - the name of the save point

Returns:

Returns the handle to the savepoint or null if the implementation does not support it

rollbackToSavepoint

void rollbackToSavepoint(Savepoint savepoint)

Roll back to a previously-created "Save Point", discarding any intervening changes to the current transaction.

Parameters:

savepoint - a previously-created savepoint

See Also:

createSavepoint(String)

releaseSavepoint

void releaseSavepoint(Savepoint savepoint)

Remove a previously-created "Save Point", writing any intervening updates into the current transaction.

Parameters:

savepoint - the name of the save point

See Also:

createSavepoint(String)

setTransactionIsolationLevel

int setTransactionIsolationLevel(int isolationLevel)

Change the current transaction isolation level.

Note: The isolation level should not - and for some DBs, cannot - be changed except at the very start of the transaction

Parameters:

isolationLevel - the transaction isolation level

Returns:

Returns the previously-set isolation

Throws:

IllegalStateException - if the isolation level is invalid or cannot be changed