org.jacorb.notification.util

Class AbstractObjectPool

java.lang.Object

org.jacorb.notification.util.AbstractObjectPool

All Implemented Interfaces:

Runnable, Configurable

Direct Known Subclasses:

AbstractPoolablePool

public abstract class AbstractObjectPool
extends Object
implements Runnable, Configurable

Abstract Base Class for Simple Pooling Mechanism. Subclasses must at least implement the method newInstance. To use a Object call lendObject. After use the Object must be returned with returnObject(Object). An Object must not be used after it has been returned to its pool! This class needs a two phase initialization: configure MUST be invoked before an instance can be used.

Author:

Alphonse Bendt

Field Summary

Fields

Modifier and Type	Field and Description
protected Configuration	config_
static boolean	DEBUG
static int	INITIAL_SIZE_DEFAULT
protected org.slf4j.Logger	logger_
static int	LOWER_WATERMARK_DEFAULT
static int	MAXIMUM_SIZE_DEFAULT
static int	MAXIMUM_WATERMARK_DEFAULT
static int	SIZE_INCREASE_DEFAULT
static long	SLEEP time the cleaner thread sleeps between two cleanups

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractObjectPool(String name)
protected	AbstractObjectPool(String name, int lowerWatermark, int sizeincrease, int initialsize, int maxWatermark, int maximumSize)

Method Summary

Methods

Modifier and Type	Method and Description
void	configure(Configuration conf)
void	dispose() Release this Pool.
void	doActivateObject(Object o) Is called before Object is returned to Client (lendObject).
void	doDestroyObject(Object o) Is called if Pool is full and returned Object is discarded.
void	doPassivateObject(Object o) Is called after Object is returned to pool.
protected boolean	isCreationAllowed() check if it is allowed to create more instances.
Object	lendObject() lend an object from the pool.
abstract Object	newInstance() This method is called by the Pool to create a new Instance.
protected void	poolIsEmpty()
void	returnObject(Object o) return an Object to the pool.
void	run()
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

DEBUG

public static final boolean DEBUG

See Also:

Constant Field Values

SLEEP

public static final long SLEEP

time the cleaner thread sleeps between two cleanups

See Also:

Constant Field Values

LOWER_WATERMARK_DEFAULT

public static final int LOWER_WATERMARK_DEFAULT

See Also:

Constant Field Values

SIZE_INCREASE_DEFAULT

public static final int SIZE_INCREASE_DEFAULT

See Also:

Constant Field Values

INITIAL_SIZE_DEFAULT

public static final int INITIAL_SIZE_DEFAULT

See Also:

Constant Field Values

MAXIMUM_WATERMARK_DEFAULT

public static final int MAXIMUM_WATERMARK_DEFAULT

See Also:

Constant Field Values

MAXIMUM_SIZE_DEFAULT

public static final int MAXIMUM_SIZE_DEFAULT

See Also:

Constant Field Values

logger_

protected final org.slf4j.Logger logger_

config_

protected Configuration config_

Constructor Detail

AbstractObjectPool

protected AbstractObjectPool(String name)

AbstractObjectPool

protected AbstractObjectPool(String name,
                  int lowerWatermark,
                  int sizeincrease,
                  int initialsize,
                  int maxWatermark,
                  int maximumSize)

Method Detail

configure

public void configure(Configuration conf)

Specified by:

configure in interface Configurable

run

public void run()

Specified by:

run in interface Runnable

dispose

public void dispose()

Release this Pool.

lendObject

public Object lendObject()

lend an object from the pool.

isCreationAllowed

protected boolean isCreationAllowed()

check if it is allowed to create more instances. preCondition: lock pool_ must be held.

poolIsEmpty

protected void poolIsEmpty()

returnObject

public void returnObject(Object o)

return an Object to the pool.

toString

public String toString()

Overrides:

toString in class Object

newInstance

public abstract Object newInstance()

This method is called by the Pool to create a new Instance. Subclasses must override appropiately .

doPassivateObject

public void doPassivateObject(Object o)

Is called after Object is returned to pool. No Op.

doActivateObject

public void doActivateObject(Object o)

Is called before Object is returned to Client (lendObject). No Op

doDestroyObject

public void doDestroyObject(Object o)

Is called if Pool is full and returned Object is discarded. No Op.