edu.vt.middleware.ldap.pool
Class AbstractLdapPool<T extends BaseLdap>

java.lang.Object
  edu.vt.middleware.ldap.pool.AbstractLdapPool<T>

Type Parameters:

T - type of ldap object

All Implemented Interfaces:

LdapPool<T>

Direct Known Subclasses:

BlockingLdapPool, SharedLdapPool

public abstract class AbstractLdapPool<T extends BaseLdap>
extends Object
implements LdapPool<T>

AbstractLdapPool contains the basic implementation for pooling ldap objects. The main design objective for the supplied pooling implementations is to provide a pool that does not block on object creation or destruction. This is what accounts for the multiple locks available on this class. The pool is backed by two queues, one for available objects and one for active objects. Objects that are available for LdapPool.checkOut() exist in the available queue. Objects that are actively in use exist in the active queue. Note that depending on the implementation an object can exist in both queues at the same time.

Version:

$Revision: 1330 $ $Date: 2010-05-23 18:10:53 -0400 (Sun, 23 May 2010) $

Author:

Middleware Services

Nested Class Summary

protected static class

AbstractLdapPool.PooledLdap<T extends BaseLdap> PooledLdap contains an ldap object that is participating in a pool.

Field Summary

protected Queue<AbstractLdapPool.PooledLdap<T>>	active List of ldap objects in use.
protected Queue<AbstractLdapPool.PooledLdap<T>>	available List of available ldap objects in the pool.
protected ReentrantLock	checkInLock Lock for check ins.
protected ReentrantLock	checkOutLock Lock for check outs.
protected LdapFactory<T>	ldapFactory Factory to create ldap objects.
protected org.apache.commons.logging.Log	logger Log for this class.
protected LdapPoolConfig	poolConfig Ldap pool config.
protected ReentrantLock	poolLock Lock for the entire pool.
protected Condition	poolNotEmpty Condition for notifying threads that an object was returned.

Constructor Summary

AbstractLdapPool(LdapPoolConfig lpc, LdapFactory<T> lf)
Creates a new pool with the supplied pool configuration and ldap factory.

Method Summary

protected void	activateAndValidate(T t) Attempts to activate and validate an ldap object.
int	activeCount() Returns the number of ldap objects in use.
int	availableCount() Returns the number of ldap objects available for use.
void	close() Empty this pool, closing all connections, and freeing any resources.
protected T	createActive() Create a new ldap object and place it in the active pool.
protected T	createAvailable() Create a new ldap object and place it in the available pool.
protected T	createAvailableAndActive() Create a new ldap object and place it in both the available and active pools.
protected void	finalize() Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.
LdapPoolConfig	getLdapPoolConfig() Returns the configuration for this pool.
void	initialize() Initialize this pool for use.
void	prune() Attempts to reduce the size of the pool back to it's configured minimum.
protected void	removeActive(T t) Remove an ldap object from the active pool.
protected void	removeAvailable(T t) Remove an ldap object from the available pool.
protected void	removeAvailableAndActive(T t) Remove an ldap object from both the available and active pools.
void	setPoolTimer(Timer t) Sets the pool to use an existing timer.
void	validate() Attempts to validate all objects in the pool.
protected boolean	validateAndPassivate(T t) Attempts to validate and passivate an ldap object.

Methods inherited from class java.lang.Object

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

Methods inherited from interface edu.vt.middleware.ldap.pool.LdapPool

checkIn, checkOut

Field Detail

poolLock

protected final ReentrantLock poolLock

Lock for the entire pool.

poolNotEmpty

protected final Condition poolNotEmpty

Condition for notifying threads that an object was returned.

checkInLock

protected final ReentrantLock checkInLock

Lock for check ins.

checkOutLock

protected final ReentrantLock checkOutLock

Lock for check outs.

logger

protected final org.apache.commons.logging.Log logger

Log for this class.

available

protected Queue<AbstractLdapPool.PooledLdap<T extends BaseLdap>> available

List of available ldap objects in the pool.

active

protected Queue<AbstractLdapPool.PooledLdap<T extends BaseLdap>> active

List of ldap objects in use.

poolConfig

protected LdapPoolConfig poolConfig

Ldap pool config.

ldapFactory

protected LdapFactory<T extends BaseLdap> ldapFactory

Factory to create ldap objects.

Constructor Detail

AbstractLdapPool

public AbstractLdapPool(LdapPoolConfig lpc,
                        LdapFactory<T> lf)

Creates a new pool with the supplied pool configuration and ldap factory. The pool configuration will be marked as immutable by this pool.

Parameters:

lpc - LdapPoolConfig

lf - LdapFactory

Method Detail

getLdapPoolConfig

public LdapPoolConfig getLdapPoolConfig()

Returns the configuration for this pool.

Specified by:

getLdapPoolConfig in interface LdapPool<T extends BaseLdap>

Returns:

ldap pool config

setPoolTimer

public void setPoolTimer(Timer t)

Sets the pool to use an existing timer. Pool will use an internal timer if none is provided. Must be called before LdapPool.initialize().

Specified by:

setPoolTimer in interface LdapPool<T extends BaseLdap>

Parameters:

t - timer used to schedule pool tasks

initialize

public void initialize()

Initialize this pool for use.

Specified by:

initialize in interface LdapPool<T extends BaseLdap>

close

public void close()

Empty this pool, closing all connections, and freeing any resources.

Specified by:

close in interface LdapPool<T extends BaseLdap>

createAvailable

protected T createAvailable()

Create a new ldap object and place it in the available pool.

Returns:

ldap object that was placed in the available pool

createActive

protected T createActive()

Create a new ldap object and place it in the active pool.

Returns:

ldap object that was placed in the active pool

createAvailableAndActive

protected T createAvailableAndActive()

Create a new ldap object and place it in both the available and active pools.

Returns:

ldap object that was placed in the available and active pools

removeAvailable

protected void removeAvailable(T t)

Remove an ldap object from the available pool.

Parameters:

t - ldap object that exists in the available pool

removeActive

protected void removeActive(T t)

Remove an ldap object from the active pool.

Parameters:

t - ldap object that exists in the active pool

removeAvailableAndActive

protected void removeAvailableAndActive(T t)

Remove an ldap object from both the available and active pools.

Parameters:

t - ldap object that exists in the both the available and active pools

activateAndValidate

protected void activateAndValidate(T t)
                            throws LdapPoolException

Attempts to activate and validate an ldap object. Performed before an object is returned from LdapPool.checkOut().

Parameters:

t - ldap object

Throws:

LdapPoolException - if this method fais

LdapActivationException - if the ldap object cannot be activated

LdapValidateException - if the ldap object cannot be validated

validateAndPassivate

protected boolean validateAndPassivate(T t)

Attempts to validate and passivate an ldap object. Performed when an object is given to LdapPool.checkIn(T).

Parameters:

t - ldap object

Returns:

whether both validate and passivation succeeded

prune

public void prune()

Attempts to reduce the size of the pool back to it's configured minimum. LdapPoolConfig.setMinPoolSize(int).

Specified by:

prune in interface LdapPool<T extends BaseLdap>

validate

public void validate()

Attempts to validate all objects in the pool. LdapPoolConfig.setValidatePeriodically(boolean).

Specified by:

validate in interface LdapPool<T extends BaseLdap>

availableCount

public int availableCount()

Returns the number of ldap objects available for use.

Specified by:

availableCount in interface LdapPool<T extends BaseLdap>

Returns:

count

activeCount

public int activeCount()

Returns the number of ldap objects in use.

Specified by:

activeCount in interface LdapPool<T extends BaseLdap>

Returns:

count

finalize

protected void finalize()
                 throws Throwable

Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.

Overrides:

finalize in class Object

Throws:

Throwable - if an exception is thrown by this method