edu.uiuc.ncsa.security.core.util

Class Pool<T>

java.lang.Object

edu.uiuc.ncsa.security.core.util.Pool<T>

public abstract class Pool<T>
extends Object

A pool of items, that is to say, a managed list that keeps valid items on it and can create or destroy them as needed. when pushing and popping off a stack.

Supremely useful with SQL connections. This does check for validity as a matter of course.

Created by Jeff Gaynor
on Mar 12, 2010 at 3:48:20 PM

Field Summary

Fields

Modifier and Type	Field and Description
static int	INFINITE
protected int	inUse

Constructor Summary

Constructors

Constructor and Description
Pool()

Method Summary

Modifier and Type	Method and Description
abstract T	create() Create a new, ready-to-use object for the pool
abstract void	destroy(T object) Destroy an object that is no longer needed.
boolean	destroyAll()
T	doCreate()
void	doDestroy(T item) Destroying an item reduces the number of in-use items.
int	getMaxSize() Get the maximum number of items
boolean	isValid(T object) Is this item still good? If not it will be removed from the pool so a new one can be created.
T	pop() Pop an object off the stack if ther eis one, otherwise, create one.
void	push(T object) Check an object into the pool.
void	setMaxSize(int c) Set the maximum number of items.

Methods inherited from class java.lang.Object

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

Field Detail

INFINITE

public static final int INFINITE

See Also:

Constant Field Values

inUse

protected int inUse

Constructor Detail

Pool

public Pool()

Method Detail

create

public abstract T create()
                  throws PoolException

Create a new, ready-to-use object for the pool

Returns:

the object

Throws:

PoolException

destroy

public abstract void destroy(T object)
                      throws PoolException

Destroy an object that is no longer needed.

Parameters:

object - the object

Throws:

PoolException

isValid

public boolean isValid(T object)
                throws PoolException

Is this item still good? If not it will be removed from the pool so a new one can be created. Default is to return true.

Throws:

PoolException

pop

public T pop()
      throws PoolException

Pop an object off the stack if ther eis one, otherwise, create one.

Returns:

the object

Throws:

PoolException

doCreate

public T doCreate()
           throws PoolException

Throws:

PoolException

doDestroy

public void doDestroy(T item)
               throws PoolException

Destroying an item reduces the number of in-use items. Do not call this on an item that hasn't been checked out.

Parameters:

item - the item

Throws:

PoolException

setMaxSize

public void setMaxSize(int c)

Set the maximum number of items.

Parameters:

c -

getMaxSize

public int getMaxSize()

Get the maximum number of items

Returns:

capacity

push

public void push(T object)
          throws PoolException

Check an object into the pool. If the pool is at capacity, destroy the object.

Parameters:

object - the object

Throws:

PoolException

destroyAll

public boolean destroyAll()