org.apache.ojb.broker.locking

Class LockManagerInMemoryImpl

java.lang.Object

org.apache.ojb.broker.locking.LockManagerInMemoryImpl

All Implemented Interfaces:

IsolationLevels, LockManager

public class LockManagerInMemoryImpl
extends java.lang.Object
implements LockManager

This implementation of the LockManager interface supports a simple, fast, non-blocking pessimistic locking for single JVM applications.

Version:

$Id: LockManagerInMemoryImpl.java 365232 2005-12-21 22:36:07Z tomdz $

Field Summary

Fields inherited from interface org.apache.ojb.broker.locking.LockManager

DEFAULT_BLOCK_TIMEOUT, DEFAULT_LOCK_TIMEOUT

Fields inherited from interface org.apache.ojb.broker.locking.IsolationLevels

IL_DEFAULT, IL_NONE, IL_OPTIMISTIC, IL_READ_COMMITTED, IL_READ_UNCOMMITTED, IL_REPEATABLE_READ, IL_SERIALIZABLE, LITERAL_IL_NONE, LITERAL_IL_OPTIMISTIC, LITERAL_IL_READ_COMMITTED, LITERAL_IL_READ_UNCOMMITTED, LITERAL_IL_REPEATABLE_READ, LITERAL_IL_SERIALIZABLE

Constructor Summary

Constructors

Constructor and Description
LockManagerInMemoryImpl()

Method Summary

Methods

Modifier and Type	Method and Description
long	getBlockTimeout() NOOP
java.lang.String	getLockInfo() Returns info about the used lock manager implementation and the state of the lock manager.
long	getLockTimeout() Get the current used lock timeout value in milliseconds.
boolean	hasRead(java.lang.Object key, java.lang.Object resourceId) Checks if there is a read lock for owner key on resource object.
boolean	hasUpgrade(java.lang.Object key, java.lang.Object resourceId) Checks if there is a upgrade lock for lock key on resource object.
boolean	hasWrite(java.lang.Object key, java.lang.Object resourceId) Checks if there is a write lock for lock key on resource object.
int	lockedObjects()
boolean	readLock(java.lang.Object key, java.lang.Object resourceId, int isolationLevel) Acquires a readlock for lock key on resource object.
boolean	releaseLock(java.lang.Object key, java.lang.Object resourceId) Releases a lock for lock key on resource object.
void	releaseLocks(java.lang.Object key) Release all resource locks hold by the specified owner key.
boolean	removeReader(java.lang.Object key, java.lang.Object resourceId) Remove an read lock.
boolean	removeWriter(java.lang.Object key, java.lang.Object resourceId) Remove an write lock.
void	setBlockTimeout(long timeout) NOOP
void	setLockTimeout(long timeout) Set the lock timeout value in milliseconds.
boolean	upgradeLock(java.lang.Object key, java.lang.Object resourceId, int isolationLevel) Acquire an upgrade lock.
boolean	writeLock(java.lang.Object key, java.lang.Object resourceId, int isolationLevel) Acquires a write lock for lock key on resource object.

Methods inherited from class java.lang.Object

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

Constructor Detail

LockManagerInMemoryImpl

public LockManagerInMemoryImpl()

Method Detail

getLockTimeout

public long getLockTimeout()

Description copied from interface: LockManager

Get the current used lock timeout value in milliseconds.

Specified by:

getLockTimeout in interface LockManager

Returns:

Current used locking timeout value in ms.

setLockTimeout

public void setLockTimeout(long timeout)

Description copied from interface: LockManager

Set the lock timeout value in milliseconds. If timeout was set to -1 the never will never timeout.

Specified by:

setLockTimeout in interface LockManager

Parameters:

timeout - The lock timeout in ms of acquired read/write/upgrade locks.

getBlockTimeout

public long getBlockTimeout()

NOOP

Specified by:

getBlockTimeout in interface LockManager

Returns:

Always '0'

setBlockTimeout

public void setBlockTimeout(long timeout)

NOOP

Specified by:

setBlockTimeout in interface LockManager

Parameters:

timeout - The time to wait for acquire a lock.

getLockInfo

public java.lang.String getLockInfo()

Description copied from interface: LockManager

Returns info about the used lock manager implementation and the state of the lock manager.

Specified by:

getLockInfo in interface LockManager

readLock

public boolean readLock(java.lang.Object key,
               java.lang.Object resourceId,
               int isolationLevel)

Description copied from interface: LockManager

Acquires a readlock for lock key on resource object. Returns true if successful, else false.

Specified by:

readLock in interface LockManager

Parameters:

key - The owner key of the lock.

resourceId - The resource to lock.

isolationLevel - The isolation level of the lock.

Returns:

True if the lock was successfully acquired.

removeReader

public boolean removeReader(java.lang.Object key,
                   java.lang.Object resourceId)

Remove an read lock.

removeWriter

public boolean removeWriter(java.lang.Object key,
                   java.lang.Object resourceId)

Remove an write lock.

releaseLock

public boolean releaseLock(java.lang.Object key,
                  java.lang.Object resourceId)

Description copied from interface: LockManager

Releases a lock for lock key on resource object. Returns true if successful, else false.

Specified by:

releaseLock in interface LockManager

Parameters:

key - The owner key of the lock.

resourceId - The resource to release.

Returns:

True if the lock was successfully released.

releaseLocks

public void releaseLocks(java.lang.Object key)

Description copied from interface: LockManager

Release all resource locks hold by the specified owner key.

Specified by:

releaseLocks in interface LockManager

Parameters:

key - The owner key to release all associated locks.

See Also:

LockManager.releaseLocks(Object)

writeLock

public boolean writeLock(java.lang.Object key,
                java.lang.Object resourceId,
                int isolationLevel)

Description copied from interface: LockManager

Acquires a write lock for lock key on resource object. Returns true if successful, else false.

Specified by:

writeLock in interface LockManager

Parameters:

key - The owner key of the lock.

resourceId - The resource to lock.

isolationLevel - The isolation level of the lock.

Returns:

True if the lock was successfully acquired.

upgradeLock

public boolean upgradeLock(java.lang.Object key,
                  java.lang.Object resourceId,
                  int isolationLevel)

Description copied from interface: LockManager

Acquire an upgrade lock. (Current implementations always acquire a write lock instead).

Specified by:

upgradeLock in interface LockManager

Parameters:

key - The owner key of the lock.

resourceId - The resource to lock.

isolationLevel - The isolation level of the lock.

Returns:

True if the lock was successfully acquired.

hasWrite

public boolean hasWrite(java.lang.Object key,
               java.lang.Object resourceId)

Description copied from interface: LockManager

Checks if there is a write lock for lock key on resource object. Returns true if so, else false.

Specified by:

hasWrite in interface LockManager

Parameters:

key - The owner key of the lock.

resourceId - The resource to check.

Returns:

True if the lock exists.

See Also:

LockManager.hasWrite(Object, Object)

hasUpgrade

public boolean hasUpgrade(java.lang.Object key,
                 java.lang.Object resourceId)

Description copied from interface: LockManager

Checks if there is a upgrade lock for lock key on resource object. Returns true if so, else false.

Specified by:

hasUpgrade in interface LockManager

Parameters:

key - The owner key of the lock.

resourceId - The resource to check.

Returns:

True if the lock exists.

hasRead

public boolean hasRead(java.lang.Object key,
              java.lang.Object resourceId)

Description copied from interface: LockManager

Checks if there is a read lock for owner key on resource object. Returns true if so, else false.

Specified by:

hasRead in interface LockManager

Parameters:

key - The owner key of the lock.

resourceId - The resource to check.

Returns:

True if the lock exists.

See Also:

LockManager.hasRead(Object, Object)

lockedObjects

public int lockedObjects()