src/ObjectPool.cpp

/*
 *   This file is part of the Standard Portable Library (SPL).
 *
 *   SPL is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation, either version 3 of the License, or
 *   (at your option) any later version.
 *
 *   SPL is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with SPL.  If not, see <http://www.gnu.org/licenses/>.
 */
#include <spl/collection/ObjectPool.h>

IPoolable::~IPoolable()
{
}

ObjectPool::ObjectPool
(
        IPoolableFactory *factory, 
        int minInstances, 
        int preferedPoolMaxInstances, 
        int maxInstances
)
:       m_factory(factory),
        m_minInstances(minInstances), 
        m_preferedPoolMaxInstances(preferedPoolMaxInstances),
        m_maxInstances(maxInstances),
        m_pool(),
        m_poolMutex(),
        m_count(0)
{
        for ( int x = 0; x < minInstances; x++ )
        {
                m_pool.Add( factory->CreateInstance() );        
        }
        m_count = minInstances;
}

ObjectPool::~ObjectPool()
{
        while ( m_pool.Count() > 0 )
        {
                IPoolable *item = m_pool.Pop();
                m_factory->Destroy( item );
        }
}

IPoolablePtr ObjectPool::GetObjectSmartPtr()
{
        return IPoolablePtr(GetObject());
}

IPoolable *ObjectPool::GetObject()
{
        IPoolable *item;
        m_poolMutex.Lock();
        if ( m_pool.Count() == 0 )
        {
                if ( m_count >= m_maxInstances )
                {
                        m_poolMutex.Unlock();
                        return NULL;
                }
                item = m_factory->CreateInstance();
                ASSERT( NULL != item );
                m_count++;
        }
        else
        {
                item = m_pool.Pop();
        }
        m_poolMutex.Unlock();
        item->OnPreRemoveFromPool();
        return item;
}

void ObjectPool::ReleaseObject( IPoolablePtr item )
{
        IPoolable *ptr = item.Detach();
        ReleaseObject(ptr);
}

void ObjectPool::ReleaseObject( IPoolable *item )
{
        item->OnPreReturnToPool();
        m_poolMutex.Lock();
        if ( m_count > m_preferedPoolMaxInstances )
        {
                m_factory->Destroy( item );
                m_count--;
        }
        else
        {
                m_pool.Add( item );
        }
        m_poolMutex.Unlock();
}

#if defined(DEBUG) || defined(_DEBUG)
void ObjectPool::CheckMem() const
{
        m_factory->CheckMem();
        //m_poolMutex.Lock();
        m_pool.CheckMem();
        int count = m_pool.Count();
        for ( int x = 0; x < count; x++ )
        {
                IPoolable *item = m_pool.ElementAt(x);
                DEBUG_NOTE_MEM( item );
                item->CheckMem();
        }
        //m_poolMutex.Unlock();
}

void ObjectPool::ValidateMem() const
{
        m_factory->ValidateMem();
        //m_poolMutex.Lock();
        m_pool.ValidateMem();
        int count = m_pool.Count();
        for ( int x = 0; x < count; x++ )
        {
                IPoolable *item = m_pool.ElementAt(x);
                ASSERT_PTR( item );
                item->ValidateMem();
        }
        //m_poolMutex.Unlock();
}
#endif