org.carrot2.util.pool
Interface IParameterizedPool<T,P>

All Known Implementing Classes:

FixedSizePool, SoftUnboundedPool

public interface IParameterizedPool<T,P>

A parameterized pool of objects. Each borrowed object is characterized by its class and an arbitrary parameter. The pair uniquely identifies a "class" (equivalence class) of pooled objects.

Please see SoftUnboundedPool for a reference implementation.

Method Summary

<I extends T> I	borrowObject(Class<I> clazz, P parameter) Borrows an object from the pool.
void	dispose() Disposes of the pool.
void	init(IInstantiationListener<T,P> objectInstantiationListener, IActivationListener<T,P> objectActivationListener, IPassivationListener<T,P> objectPassivationListener, IDisposalListener<T,P> objectDisposalListener) Initializes the pool with a number of listeners.
void	returnObject(T object, P parameter) Returns an object to the pool.

Method Detail

init

void init(IInstantiationListener<T,P> objectInstantiationListener,
          IActivationListener<T,P> objectActivationListener,
          IPassivationListener<T,P> objectPassivationListener,
          IDisposalListener<T,P> objectDisposalListener)

Initializes the pool with a number of listeners. The appropriate listeners must be called at the relevant stages of a pooled object's life cycle.

borrowObject

<I extends T> I borrowObject(Class<I> clazz,
                             P parameter)
                         throws InstantiationException,
                                IllegalAccessException

Borrows an object from the pool. If no instance is available, a parameterless constructor should be used to create a new one.

Parameters:

clazz - class of object to be borrowed

parameter - additional parameter determining a possible sub type within the same class of objects being borrowed. A combination of class and parameter uniquely identifies a "class" (equivalence class) of pooled objects. The parameter is assumed to correctly implement the Object.equals(Object) and Object.hashCode() methods. The parameter can be null. The implementation must pass the parameter to all listeners when managing the life cycle of the pooled object. It is the callers responsibility to ensure that exactly the same value of the parameter is passed to the corresponding borrowObject(Class, Object) and returnObject(Object, Object) methods.

Throws:

InstantiationException

IllegalAccessException

returnObject

void returnObject(T object,
                  P parameter)

Returns an object to the pool.

Parameters:

object - object to return

parameter - parameter provided when borrowing the object. If the parameter was not null when borrowing the object, the same value will be passed here.

dispose

void dispose()

Disposes of the pool. No objects can be borrowed from the pool after disposed.