net.spy.pool
Class PoolAble

java.lang.Object
  net.spy.SpyObject
      net.spy.pool.PoolAble

Direct Known Subclasses:

JDBCPoolAble, SNPPPoolAble

public abstract class PoolAble
extends SpyObject

PoolAble is the object container that is used to store objects in the pool.

The system property net.spy.pool.debug can be set to a file where the debugging output will go.

Field Summary

static int	MAY_CLEAN Minimum value returned from pruneStatus() if we may clean the object.
static int	MUST_CLEAN Minimum value returned from pruneStatus() if we must clean the object.

Constructor Summary

PoolAble(java.lang.Object o, int h)
Get a PoolAble representation for an object.

PoolAble(java.lang.Object o, long a, int h)
Get a PoolAble representation for an object, including a given maximum lifetime the object can have.

Method Summary

void	activate() Activate this PoolAble object.
void	checkIn() Check the object back in.
void	checkOut() Check the object out.
protected void	debug(java.lang.String msg) Debugging info.
void	discard() Discard the object.
java.lang.Object	getObject() Get the object we're pooling.
int	getObjectID() Get the object ID of this object.
protected java.lang.Object	intGetObject() Internal version of getObject().
boolean	isAlive() Find out of the PoolAble represents a usable object.
boolean	isAvailable() Find out if the object is available for a requestor
boolean	isCheckedOut() Find out if the object is checked out.
int	pruneStatus() Find out if an object is prunable
protected void	setAvailable() Mark this object as available.
void	setMaxAge(long to) Set the maximum age of this PoolAble.
void	setObjectID(int id) Set the internal object ID.
void	setPoolName(java.lang.String to) Set the pool name this thing sits in.
protected void	setUnavailable() Mark this object as unavailable.
java.lang.String	toString() Return a string representation of this object.

Methods inherited from class net.spy.SpyObject

getLogger

Methods inherited from class java.lang.Object

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

Field Detail

MAY_CLEAN

public static final int MAY_CLEAN

Minimum value returned from pruneStatus() if we may clean the object.

See Also:

Constant Field Values

MUST_CLEAN

public static final int MUST_CLEAN

Minimum value returned from pruneStatus() if we must clean the object.

See Also:

Constant Field Values

Constructor Detail

PoolAble

public PoolAble(java.lang.Object o,
                int h)

Get a PoolAble representation for an object.

PoolAble

public PoolAble(java.lang.Object o,
                long a,
                int h)

Get a PoolAble representation for an object, including a given maximum lifetime the object can have.

Parameters:

maxAge - the amount of time, in milliseconds, that the object will be valid. Objects will not be checked out if they are older than their maximum lifetime.

Method Detail

setMaxAge

public void setMaxAge(long to)

Set the maximum age of this PoolAble.

isAlive

public boolean isAlive()

Find out of the PoolAble represents a usable object. Objects extending PoolAble should implement isAlive() methods for their particular needs.

Objects implementing isAlive() should turn off object availability if they determine the object no longer isAlive().

Returns:

true if the object will be usable

getObject

public java.lang.Object getObject()
                           throws PoolException

Get the object we're pooling.

Returns:

the object.

Throws:

PoolException - if something bad happens (i.e. the object is not checked out)

intGetObject

protected java.lang.Object intGetObject()

Internal version of getObject(). Returns regardless of whether the object has been checked out.

setObjectID

public void setObjectID(int id)

Set the internal object ID. This probably shouldn't be called outside of the pool container.

Parameters:

id - ObjectId of this object.

setPoolName

public void setPoolName(java.lang.String to)

Set the pool name this thing sits in. This is for debugging, but it's useful information, nonetheless.

getObjectID

public int getObjectID()

Get the object ID of this object.

Returns:

the object ID

activate

public void activate()

Activate this PoolAble object.

checkIn

public void checkIn()

Check the object back in. The PoolAble will not be usable again until it's checked back out from the pooler.

checkIn also does some checks such as making sure the item is not too old, and that it is still alive.

setAvailable

protected void setAvailable()

Mark this object as available.

setUnavailable

protected void setUnavailable()

Mark this object as unavailable.

checkOut

public void checkOut()

Check the object out. Called from the PoolContainer

isCheckedOut

public boolean isCheckedOut()

Find out if the object is checked out.

isAvailable

public boolean isAvailable()

Find out if the object is available for a requestor

pruneStatus

public int pruneStatus()

Find out if an object is prunable

Returns:

0 if not available, 1 if we may clean, greater than one if we must clean.

discard

public void discard()

Discard the object. Anything that extends from this class needs to call super.discard() when it's done.

debug

protected final void debug(java.lang.String msg)

Debugging info.

toString

public java.lang.String toString()

Return a string representation of this object.

Overrides:

toString in class java.lang.Object

Returns:

a string representation of this object.