org.sadun.util.pool2
Class ObjectPool

java.lang.Object
  org.sadun.util.pool.ObjectPool
      org.sadun.util.pool2.ObjectPool

All Implemented Interfaces:

java.io.Serializable

public class ObjectPool

extends ObjectPool

NOT COMPLETE YET.

A pool of object which handles transparent passivation/activation.

This pool create and allocate pooled objects referencing the original objects and implementing the same interface(s).

The pool can be used either accessing objects by interface or by class.

The given object class should implement one or more specific interface(s). The instances returned by the acquire() method can be directly cast to that interface(s). For example, if a class MyTestObject implements the javax.swing.Action interface, the following code can be used:

  ObjectPool pool = new ObjectPool("test pool", 10, MyTestObject.class);
  ...
  Action action = (Action)pool.acquire();
  Object obj = action.getValue();
  ...
  action.release();
  ...
  pool.dispose();
 

If the given object is used directly as a class (rather than interface), the following conditions hold:

• The object returned by the pool's acquire() method cannot be cast to the original class directly, but to the PooledObject interface.
• The returned object implements all the methods of the original object, but since it's type is possibly generated at runtime, the methods are only available trhough reflection.
• The original object can be obtained by invoking _getOriginal() on the returned object, and must be released by _releaseOriginal().

For example:

   ObjectPool pool = new ObjectPool("test pool", 10, MyTestObject.class);
   ...
   PooledObject pObj = (PooledObject)pool.acquire();
   MyTestObject obj = (MyTestObject)pObj._getOriginal();
   obj.myTestMethod();
   pObj._releaseOriginal();
 

.

Version:

1.0

Author:

Cristiano Sadun

See Also:

Serialized Form

Nested Class Summary

static class	ObjectPool.DefaultPassivationManagerFactory An ObjectPool.PassivationManagerFactory which produces DefaultPassivationManagers
protected static class	ObjectPool.PassivationManagerFactory A base class for a factory of BasePassivationManagers.
protected static class	ObjectPool.PooledObjectFactory A object factory which produces BasePooledObject wrappers for other classes.

Nested classes inherited from class org.sadun.util.pool.ObjectPool

ObjectPool.BaseFactory, ObjectPool.Factory, ObjectPool.ObjectFactory, ObjectPool.ObjectPoolException, ObjectPool.PooledObjectWrapper

Field Summary

Fields inherited from class org.sadun.util.pool.ObjectPool

free, pool, used

Constructor Summary

ObjectPool(java.lang.String poolName, Configuration configuration, java.lang.Class objectType)
Create a named object pool of objects of the given class and the given Configuration (which also provides the size of the pool).

ObjectPool(java.lang.String poolName, Configuration configuration, java.lang.Class objectType, java.lang.Object[] params)
Create a named object pool of objects of the given class and the given Configuration (which also provides the size of the pool).

ObjectPool(java.lang.String poolName, Configuration configuration, java.lang.Class objectType, java.lang.Object[] params, Setup setupObject)
Create a named object pool of objects of the given class and the given Configuration (which also provides the size of the pool).

ObjectPool(java.lang.String poolName, Configuration configuration, java.lang.Class objectType, Setup setupObject)
Create a named object pool of objects of the given class and the given Configuration (which also provides the size of the pool).

ObjectPool(java.lang.String poolName, Configuration configuration, ObjectPool.Factory factory)
Create a named object pool of objects of the given class and the given Configuration (which also provides the size of the pool).

ObjectPool(java.lang.String poolName, int n, java.lang.Class objectType)
Create a named object pool of n objects of the given class and a default Configuration.

ObjectPool(java.lang.String poolName, int n, java.lang.Class objectType, java.lang.Object[] params)
Create a named object pool of n objects of the given class and a default Configuration.

Method Summary

PooledObject	acquireInstance() A convenience method which already casts the result of acquire() to the PooledObject type.
void	dispose()
Configuration	getConfiguration() Returns the configuration.
static java.io.PrintStream	getDefaultLogStream() Returns the defaultLogStream.
java.io.PrintStream	getLogStream() Returns the logStream.
java.lang.String	getName() Returns the name.
BasePassivationManager	getPassivationManager() Returns the passivationManager.
static void	main(java.lang.String[] args) Test method
static void	setDefaultLogStream(java.io.PrintStream defaultLogStream) Sets the defaultLogStream.
void	setLogStream(java.io.PrintStream logStream) Sets the logStream.

Methods inherited from class org.sadun.util.pool.ObjectPool

acquire, acquire, acquire, destroy, getFactory, getFreeCount, getObjectType, getSize, getUsedCount, newPool, newPool, release, release, release, renew, setFactory, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

ObjectPool

public ObjectPool(java.lang.String poolName,
                  Configuration configuration,
                  java.lang.Class objectType)
           throws ObjectPool.ObjectPoolException

Create a named object pool of objects of the given class and the given Configuration (which also provides the size of the pool).

The objects are created by invoking their default constructor.

Parameters:

poolName - the name of the pool

configuration - a Configuration object

objectType - the class of objects to create

ObjectPool

public ObjectPool(java.lang.String poolName,
                  Configuration configuration,
                  java.lang.Class objectType,
                  Setup setupObject)
           throws ObjectPool.ObjectPoolException

Create a named object pool of objects of the given class and the given Configuration (which also provides the size of the pool).

The objects are created by invoking their default constructor.

After the creation, each object is passed by the given Setup object.

Parameters:

poolName - the name of the pool

configuration - a Configuration object

objectType - the class of objects to create

setupObject - the Setup object used for post-construction setup

ObjectPool

public ObjectPool(java.lang.String poolName,
                  Configuration configuration,
                  java.lang.Class objectType,
                  java.lang.Object[] params)

Create a named object pool of objects of the given class and the given Configuration (which also provides the size of the pool).

The objects are created by invoking the constructor matching the types of the given parameter objects.

Parameters:

poolName - the name of the pool

configuration - a Configuration object

objectType - the class of objects to create

params - the array of parameters used for constructing the object

ObjectPool

public ObjectPool(java.lang.String poolName,
                  Configuration configuration,
                  java.lang.Class objectType,
                  java.lang.Object[] params,
                  Setup setupObject)
           throws ObjectPool.ObjectPoolException

Create a named object pool of objects of the given class and the given Configuration (which also provides the size of the pool).

The objects are created by invoking the constructor matching the types of the given parameter objects.

After the creation, each object is passed by the given Setup object.

Parameters:

poolName - the name of the pool

configuration - a Configuration object

objectType - the class of objects to create

params - the array of parameters used for constructing the object

setupObject - the Setup object used for post-construction setup

ObjectPool

public ObjectPool(java.lang.String poolName,
                  int n,
                  java.lang.Class objectType,
                  java.lang.Object[] params)

Create a named object pool of n objects of the given class and a default Configuration.

The objects are created by invoking the constructor matching the types of the given parameter objects.

Parameters:

n - the number of objects to create

poolName - the name of the pool

objectType - the class of objects to create

params - the array of parameters used for constructing the object

ObjectPool

public ObjectPool(java.lang.String poolName,
                  int n,
                  java.lang.Class objectType)

Create a named object pool of n objects of the given class and a default Configuration.

The objects are created by invoking their default constructor.

Parameters:

n - the number of objects to create

poolName - the name of the pool

objectType - the class of objects to create

ObjectPool

public ObjectPool(java.lang.String poolName,
                  Configuration configuration,
                  ObjectPool.Factory factory)
           throws ObjectPool.ObjectPoolException

Create a named object pool of objects of the given class and the given Configuration (which also provides the size of the pool).

The objects are created by using the given object factory.

Parameters:

poolName - the name of the pool

configuration - a Configuration object

factory - the object factory which produces the instances to pool.

Method Detail

getDefaultLogStream

public static java.io.PrintStream getDefaultLogStream()

Returns the defaultLogStream.

Returns:

PrintStream

setDefaultLogStream

public static void setDefaultLogStream(java.io.PrintStream defaultLogStream)

Sets the defaultLogStream.

Parameters:

defaultLogStream - The defaultLogStream to set

getLogStream

public java.io.PrintStream getLogStream()

Returns the logStream.

Returns:

PrintStream

setLogStream

public void setLogStream(java.io.PrintStream logStream)

Sets the logStream.

Parameters:

logStream - The logStream to set

getConfiguration

public Configuration getConfiguration()

Returns the configuration.

Returns:

Configuration

acquireInstance

public PooledObject acquireInstance()

A convenience method which already casts the result of acquire() to the PooledObject type.

Returns:

one object in the pool, obtained invoking acquire()

getName

public java.lang.String getName()

Returns the name.

Returns:

String

dispose

public void dispose()

getPassivationManager

public BasePassivationManager getPassivationManager()

Returns the passivationManager.

Returns:

BasePassivationManager

main

public static void main(java.lang.String[] args)
                 throws java.lang.Exception

Test method

Throws:

java.lang.Exception