Package org.apache.manifoldcf.core.lockmanager

Class LockObject

java.lang.Object

org.apache.manifoldcf.core.lockmanager.LockObject

Direct Known Subclasses:

FileLockObject, ZooKeeperLockObject

public class LockObject
extends java.lang.Object

Base class. One instance of this object exists for each lock on each JVM!

Field Summary

Fields

Modifier and Type	Field	Description
static java.lang.String	_rcsid
protected static java.lang.String	LOCKEDANOTHERJVM
protected static java.lang.String	LOCKEDANOTHERTHREAD
protected java.lang.Object	lockKey

Constructor Summary

Constructors

Constructor	Description
LockObject(LockPool lockPool, java.lang.Object lockKey)

Method Summary

Modifier and Type	Method	Description
protected void	clearGlobalNonExWriteLock()
protected void	clearGlobalNonExWriteLockNoWait()
protected void	clearGlobalReadLock()
protected void	clearGlobalReadLockNoWait()
protected void	clearGlobalWriteLock()
protected void	clearGlobalWriteLockNoWait()
void	enterNonExWriteLock()
void	enterNonExWriteLockNoWait()	Note well: Upgrading a read lock to a non-ex write lock is tricky.
void	enterReadLock()
void	enterReadLockNoWait()
void	enterWriteLock()	This method WILL NOT BE CALLED UNLESS we are actually committing a write lock for the first time for a given thread.
void	enterWriteLockNoWait()	Note well: Upgrading a read lock to a non-ex write lock is tricky.
boolean	leaveNonExWriteLock()
boolean	leaveReadLock()
boolean	leaveWriteLock()
void	makeInvalid()
protected void	obtainGlobalNonExWriteLock()
protected void	obtainGlobalNonExWriteLockNoWait()
protected void	obtainGlobalReadLock()
protected void	obtainGlobalReadLockNoWait()
protected void	obtainGlobalWriteLock()
protected void	obtainGlobalWriteLockNoWait()

Methods inherited from class java.lang.Object

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

Field Detail

_rcsid

public static final java.lang.String _rcsid

See Also:

Constant Field Values

lockKey

protected final java.lang.Object lockKey

LOCKEDANOTHERTHREAD

protected static final java.lang.String LOCKEDANOTHERTHREAD

See Also:

Constant Field Values

LOCKEDANOTHERJVM

protected static final java.lang.String LOCKEDANOTHERJVM

See Also:

Constant Field Values

Constructor Detail

LockObject

public LockObject(LockPool lockPool,
                  java.lang.Object lockKey)

Method Detail

makeInvalid

public void makeInvalid()

enterWriteLock

public void enterWriteLock()
                    throws ManifoldCFException,
                           java.lang.InterruptedException,
                           ExpiredObjectException

This method WILL NOT BE CALLED UNLESS we are actually committing a write lock for the first time for a given thread.

Throws:

ManifoldCFException

java.lang.InterruptedException

ExpiredObjectException

enterWriteLockNoWait

public void enterWriteLockNoWait()
                          throws ManifoldCFException,
                                 LockException,
                                 LocalLockException,
                                 java.lang.InterruptedException,
                                 ExpiredObjectException

Note well: Upgrading a read lock to a non-ex write lock is tricky. The code inside the lock should execute only when there are NO threads that are executing in a read-locked area that aren't waiting to enter the non-ex write lock area! This is therefore essentially an illegal codepath, because it will lead inevitably to deadlock, as is going from a read-locked area into a write-locked area, or from a non-ex write area into an exclusive write area.

Throws:

ManifoldCFException

LockException

LocalLockException

java.lang.InterruptedException

ExpiredObjectException

obtainGlobalWriteLockNoWait

protected void obtainGlobalWriteLockNoWait()
                                    throws ManifoldCFException,
                                           LockException,
                                           java.lang.InterruptedException

Throws:

ManifoldCFException

LockException

java.lang.InterruptedException

obtainGlobalWriteLock

protected void obtainGlobalWriteLock()
                              throws ManifoldCFException,
                                     java.lang.InterruptedException

Throws:

ManifoldCFException

java.lang.InterruptedException

leaveWriteLock

public boolean leaveWriteLock()
                       throws ManifoldCFException,
                              java.lang.InterruptedException,
                              ExpiredObjectException

Throws:

ManifoldCFException

java.lang.InterruptedException

ExpiredObjectException

clearGlobalWriteLockNoWait

protected void clearGlobalWriteLockNoWait()
                                   throws ManifoldCFException,
                                          LockException,
                                          java.lang.InterruptedException

Throws:

ManifoldCFException

LockException

java.lang.InterruptedException

clearGlobalWriteLock

protected void clearGlobalWriteLock()
                             throws ManifoldCFException,
                                    java.lang.InterruptedException

Throws:

ManifoldCFException

java.lang.InterruptedException

enterNonExWriteLock

public void enterNonExWriteLock()
                         throws ManifoldCFException,
                                java.lang.InterruptedException,
                                ExpiredObjectException

Throws:

ManifoldCFException

java.lang.InterruptedException

ExpiredObjectException

enterNonExWriteLockNoWait

public void enterNonExWriteLockNoWait()
                               throws ManifoldCFException,
                                      LockException,
                                      LocalLockException,
                                      java.lang.InterruptedException,
                                      ExpiredObjectException

Note well: Upgrading a read lock to a non-ex write lock is tricky. The code inside the lock should execute only when there are NO threads that are executing in a read-locked area that aren't waiting to enter the non-ex write lock area! This is therefore essentially an illegal codepath, because it will lead inevitably to deadlock, as is going from a read-locked area into a write-locked area, or from a non-ex write area into an exclusive write area.

Throws:

ManifoldCFException

LockException

LocalLockException

java.lang.InterruptedException

ExpiredObjectException

obtainGlobalNonExWriteLockNoWait

protected void obtainGlobalNonExWriteLockNoWait()
                                         throws ManifoldCFException,
                                                LockException,
                                                java.lang.InterruptedException

Throws:

ManifoldCFException

LockException

java.lang.InterruptedException

obtainGlobalNonExWriteLock

protected void obtainGlobalNonExWriteLock()
                                   throws ManifoldCFException,
                                          java.lang.InterruptedException

Throws:

ManifoldCFException

java.lang.InterruptedException

leaveNonExWriteLock

public boolean leaveNonExWriteLock()
                            throws ManifoldCFException,
                                   java.lang.InterruptedException,
                                   ExpiredObjectException

Throws:

ManifoldCFException

java.lang.InterruptedException

ExpiredObjectException

clearGlobalNonExWriteLockNoWait

protected void clearGlobalNonExWriteLockNoWait()
                                        throws ManifoldCFException,
                                               LockException,
                                               java.lang.InterruptedException

Throws:

ManifoldCFException

LockException

java.lang.InterruptedException

clearGlobalNonExWriteLock

protected void clearGlobalNonExWriteLock()
                                  throws ManifoldCFException,
                                         java.lang.InterruptedException

Throws:

ManifoldCFException

java.lang.InterruptedException

enterReadLock

public void enterReadLock()
                   throws ManifoldCFException,
                          java.lang.InterruptedException,
                          ExpiredObjectException

Throws:

ManifoldCFException

java.lang.InterruptedException

ExpiredObjectException

enterReadLockNoWait

public void enterReadLockNoWait()
                         throws ManifoldCFException,
                                LockException,
                                LocalLockException,
                                java.lang.InterruptedException,
                                ExpiredObjectException

Throws:

ManifoldCFException

LockException

LocalLockException

java.lang.InterruptedException

ExpiredObjectException

obtainGlobalReadLockNoWait

protected void obtainGlobalReadLockNoWait()
                                   throws ManifoldCFException,
                                          LockException,
                                          java.lang.InterruptedException

Throws:

ManifoldCFException

LockException

java.lang.InterruptedException

obtainGlobalReadLock

protected void obtainGlobalReadLock()
                             throws ManifoldCFException,
                                    java.lang.InterruptedException

Throws:

ManifoldCFException

java.lang.InterruptedException

leaveReadLock

public boolean leaveReadLock()
                      throws ManifoldCFException,
                             java.lang.InterruptedException,
                             ExpiredObjectException

Throws:

ManifoldCFException

java.lang.InterruptedException

ExpiredObjectException

clearGlobalReadLockNoWait

protected void clearGlobalReadLockNoWait()
                                  throws ManifoldCFException,
                                         LockException,
                                         java.lang.InterruptedException

Throws:

ManifoldCFException

LockException

java.lang.InterruptedException

clearGlobalReadLock

protected void clearGlobalReadLock()
                            throws ManifoldCFException,
                                   java.lang.InterruptedException

Throws:

ManifoldCFException

java.lang.InterruptedException