Class ContainerLocking2

java.lang.Object

org.apache.derby.impl.store.raw.xact.NoLocking

org.apache.derby.impl.store.raw.xact.ContainerLocking2

All Implemented Interfaces:

LockingPolicy

public class ContainerLocking2
extends NoLocking

A locking policy that implements container level locking with isolation degree 2.

See Also:

• LockingPolicy

Field Summary

Fields

Modifier and Type	Field	Description
private final LockFactory	lf

Fields inherited from interface LockingPolicy

MODE_CONTAINER, MODE_NONE, MODE_RECORD

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	ContainerLocking2()
protected	ContainerLocking2(LockFactory lf)

Method Summary

Modifier and Type	Method	Description
int	getMode()	Get the mode of this policy
boolean	lockContainer(Transaction t, ContainerHandle container, boolean waitForLock, boolean forUpdate)	Obtain a Container shared or exclusive lock until the end of the nested transaction.
void	unlockContainer(Transaction t, ContainerHandle container)	Unlock read locks.

Methods inherited from class NoLocking

lockRecordForRead, lockRecordForWrite, unlockRecordAfterRead, zeroDurationLockRecordForWrite

Methods inherited from class Object

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

Field Details

lf

private final LockFactory lf

Constructor Details

ContainerLocking2

protected ContainerLocking2()

ContainerLocking2

protected ContainerLocking2(LockFactory lf)

Method Details

lockContainer

public boolean lockContainer(Transaction t,
 ContainerHandle container,
 boolean waitForLock,
 boolean forUpdate)
                      throws StandardException

Obtain a Container shared or exclusive lock until the end of the nested transaction.

Specified by:

lockContainer in interface LockingPolicy

Overrides:

lockContainer in class NoLocking

Parameters:

t - Transaction to associate lock with.

container - Container to lock.

waitForLock - Should lock request wait until granted?

forUpdate - Should container be locked for update, or read?

Returns:

true if the lock was obtained, false if it wasn't. False should only be returned if the waitForLock policy was set to "false," and the lock was unavailable.

Throws:

StandardException - Standard Derby error policy

See Also:

• ContainerHandle

unlockContainer

public void unlockContainer(Transaction t,
 ContainerHandle container)

Unlock read locks.

In Cursor stability release all read locks obtained. unlockContainer() will be called when the container is closed.

Specified by:

unlockContainer in interface LockingPolicy

Overrides:

unlockContainer in class NoLocking

Parameters:

t - The transaction to associate the lock with.

container - Container to unlock.

See Also:

• ContainerHandle
• ContainerHandle.close()

getMode

public int getMode()

Description copied from interface: LockingPolicy

Get the mode of this policy

Specified by:

getMode in interface LockingPolicy

Overrides:

getMode in class NoLocking