ReadWriteLockManager (Commons Transaction 1.3-SNAPSHOT API)

java.lang.Object
- org.apache.commons.transaction.locking.GenericLockManager
- - org.apache.commons.transaction.locking.ReadWriteLockManager

All Implemented Interfaces:

LockManager, LockManager2

Direct Known Subclasses:

ReadWriteUpgradeLockManager
```
public class ReadWriteLockManager
extends GenericLockManager
```
Manager for ReadWriteLocks on resources.

Since:

1.1

Version:

$Id: ReadWriteLockManager.java 493628 2007-01-07 01:42:48Z joerg $

Field Summary
- Fields inherited from class org.apache.commons.transaction.locking.GenericLockManager
  checkThreshhold, DEFAULT_CHECK_THRESHHOLD, DEFAULT_TIMEOUT, effectiveGlobalTimeouts, globalLocks, globalOwners, globalTimeoutMSecs, logger, maxLockLevel, timedOutOwners

Constructor Summary

Constructors
Modifier	Constructor and Description
`protected`	`ReadWriteLockManager(int maxLockLevel, LoggerFacade logger, long timeoutMSecs)`
	`ReadWriteLockManager(LoggerFacade logger, long timeoutMSecs)` Creates a new read/write lock manager.

Method Summary

Methods
Modifier and Type	Method and Description
`boolean`	`checkReadLock(Object ownerId, Object resourceId)` Determines if a shared, reentrant read lock on a resource could be acquired without actually acquiring it.
`boolean`	`checkWriteLock(Object ownerId, Object resourceId)` Determines if an exclusive, reentrant write lock on a resource could be acquired without actually acquiring it.
`protected GenericLock`	`createLock(Object resourceId)`
`boolean`	`hasReadLock(Object ownerId, Object resourceId)` Determines if a shared, reentrant read lock on a resource is held by an owner.
`boolean`	`hasWriteLock(Object ownerId, Object resourceId)` Determines if an exclusive, reentrant write lock on a resource is held by an owner.
`void`	`readLock(Object ownerId, Object resourceId)` Tries to acquire a shared, reentrant read lock on a resource.
`boolean`	`tryReadLock(Object ownerId, Object resourceId)` Tries to acquire a shared, reentrant read lock on a resource.
`boolean`	`tryWriteLock(Object ownerId, Object resourceId)` Tries to acquire an exclusive, reentrant write lock on a resource.
`void`	`writeLock(Object ownerId, Object resourceId)` Tries to acquire an exclusive, reentrant write lock on a resource.

Methods inherited from class org.apache.commons.transaction.locking.GenericLockManager
addOwner, atomicGetOrCreateLock, checkLock, doLock, getAll, getLevel, getLock, getLocks, getNextGlobalConflictTimeout, hasLock, lock, lock, lock, release, releaseAll, releaseAllNoTimeOutReset, releaseTimedOutOwners, removeLock, removeOwner, removeOwnerWithoutLocks, startGlobalTimeout, timeOut, timeoutCheck, toString, tryLock, wouldDeadlock

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - ReadWriteLockManager
```
public ReadWriteLockManager(LoggerFacade logger,
                    long timeoutMSecs)
```
    Creates a new read/write lock manager.
    
    Parameters:
    logger - generic logger used for all kind of debug logging
    timeoutMSecs - specifies the maximum time to wait for a lock in milliseconds
  - ReadWriteLockManager
```
protected ReadWriteLockManager(int maxLockLevel,
                    LoggerFacade logger,
                    long timeoutMSecs)
                        throws IllegalArgumentException
```
    Throws:
    
    IllegalArgumentException
- Method Detail
  - tryReadLock
```
public boolean tryReadLock(Object ownerId,
                  Object resourceId)
```
    Tries to acquire a shared, reentrant read lock on a resource.
    
    This method does not block, but immediatly returns. If a lock is not available false will be returned.
    
    Parameters:
    ownerId - a unique id identifying the entity that wants to acquire this lock
    resourceId - the resource to get the lock for
    
    Returns:
    true if the lock has been acquired, false otherwise
  - tryWriteLock
```
public boolean tryWriteLock(Object ownerId,
                   Object resourceId)
```
    Tries to acquire an exclusive, reentrant write lock on a resource.
    
    This method does not block, but immediatly returns. If a lock is not available false will be returned.
    
    Parameters:
    ownerId - a unique id identifying the entity that wants to acquire this lock
    resourceId - the resource to get the lock for
    
    Returns:
    true if the lock has been acquired, false otherwise
  - checkReadLock
```
public boolean checkReadLock(Object ownerId,
                    Object resourceId)
```
    Determines if a shared, reentrant read lock on a resource could be acquired without actually acquiring it.
    
    This method does not block, but immediatly returns. If a lock is not available false will be returned.
    
    Parameters:
    ownerId - a unique id identifying the entity that wants to acquire this lock
    resourceId - the resource to get the lock for
    
    Returns:
    true if the lock could be acquired, false otherwise
  - hasWriteLock
```
public boolean hasWriteLock(Object ownerId,
                   Object resourceId)
```
    Determines if an exclusive, reentrant write lock on a resource is held by an owner.
    
    Parameters:
    ownerId - a unique id identifying the entity that wants to check this lock
    resourceId - the resource to get the lock for
    
    Returns:
    true if the lock is held by the owner, false otherwise
  - hasReadLock
```
public boolean hasReadLock(Object ownerId,
                  Object resourceId)
```
    Determines if a shared, reentrant read lock on a resource is held by an owner.
    
    Parameters:
    ownerId - a unique id identifying the entity that wants to check this lock
    resourceId - the resource to get the lock for
    
    Returns:
    true if the lock is held by the owner, false otherwise
  - checkWriteLock
```
public boolean checkWriteLock(Object ownerId,
                     Object resourceId)
```
    Determines if an exclusive, reentrant write lock on a resource could be acquired without actually acquiring it.
    
    This method does not block, but immediatly returns. If a lock is not available false will be returned.
    
    Parameters:
    ownerId - a unique id identifying the entity that wants to acquire this lock
    resourceId - the resource to get the lock for
    
    Returns:
    true if the lock could be acquired, false otherwise
  - readLock
```
public void readLock(Object ownerId,
            Object resourceId)
              throws LockException
```
    Tries to acquire a shared, reentrant read lock on a resource.
    
    This method blocks and waits for the lock in case it is not avaiable. If there is a timeout or a deadlock or the thread is interrupted a LockException is thrown.
    
    Parameters:
    ownerId - a unique id identifying the entity that wants to acquire this lock
    resourceId - the resource to get the lock for
    
    Throws:
    
    LockException - will be thrown when the lock can not be acquired
  - writeLock
```
public void writeLock(Object ownerId,
             Object resourceId)
               throws LockException
```
    Tries to acquire an exclusive, reentrant write lock on a resource.
    
    This method blocks and waits for the lock in case it is not avaiable. If there is a timeout or a deadlock or the thread is interrupted a LockException is thrown.
    
    Parameters:
    ownerId - a unique id identifying the entity that wants to acquire this lock
    resourceId - the resource to get the lock for
    
    Throws:
    
    LockException - will be thrown when the lock can not be acquired
  - createLock
```
protected GenericLock createLock(Object resourceId)
```
    Overrides:
    
    createLock in class GenericLockManager

Class ReadWriteLockManager

Field Summary

Fields inherited from class org.apache.commons.transaction.locking.GenericLockManager

Constructor Summary

Method Summary

Methods inherited from class org.apache.commons.transaction.locking.GenericLockManager

Methods inherited from class java.lang.Object

Constructor Detail

ReadWriteLockManager

ReadWriteLockManager

Method Detail

tryReadLock

tryWriteLock

checkReadLock

hasWriteLock

hasReadLock

checkWriteLock

readLock

writeLock

createLock