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//
// SessionPool.cpp
//
// Library: Data
// Package: SessionPooling
// Module: SessionPool
//
// Copyright (c) 2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier: BSL-1.0
//
#include "Poco/Data/SessionPool.h"
#include "Poco/Data/SessionFactory.h"
#include "Poco/Data/DataException.h"
#include <algorithm>
namespace Poco {
namespace Data {
SessionPool::SessionPool(const std::string& connector, const std::string& connectionString, int minSessions, int maxSessions, int idleTime):
_connector(connector),
_connectionString(connectionString),
_minSessions(minSessions),
_maxSessions(maxSessions),
_idleTime(idleTime),
_nSessions(0),
_janitorTimer(1000*idleTime, 1000*idleTime/4),
_shutdown(false)
{
Poco::TimerCallback<SessionPool> callback(*this, &SessionPool::onJanitorTimer);
_janitorTimer.start(callback);
}
SessionPool::~SessionPool()
{
try
{
shutdown();
}
catch (...)
{
poco_unexpected();
}
}
Session SessionPool::get(const std::string& name, bool value)
{
Session s = get();
_addFeatureMap.insert(AddFeatureMap::value_type(s.impl(),
std::make_pair(name, s.getFeature(name))));
s.setFeature(name, value);
return s;
}
Session SessionPool::get()
{
Poco::Mutex::ScopedLock lock(_mutex);
if (_shutdown) throw InvalidAccessException("Session pool has been shut down.");
purgeDeadSessions();
if (_idleSessions.empty())
{
if (_nSessions < _maxSessions)
{
Session newSession(SessionFactory::instance().create(_connector, _connectionString));
applySettings(newSession.impl());
customizeSession(newSession);
PooledSessionHolderPtr pHolder(new PooledSessionHolder(*this, newSession.impl()));
_idleSessions.push_front(pHolder);
++_nSessions;
}
else throw SessionPoolExhaustedException(_connector);
}
PooledSessionHolderPtr pHolder(_idleSessions.front());
PooledSessionImplPtr pPSI(new PooledSessionImpl(pHolder));
_activeSessions.push_front(pHolder);
_idleSessions.pop_front();
return Session(pPSI);
}
void SessionPool::purgeDeadSessions()
{
Poco::Mutex::ScopedLock lock(_mutex);
if (_shutdown) return;
SessionList::iterator it = _idleSessions.begin();
for (; it != _idleSessions.end(); )
{
if (!(*it)->session()->isConnected())
{
it = _idleSessions.erase(it);
--_nSessions;
}
else ++it;
}
}
int SessionPool::capacity() const
{
return _maxSessions;
}
int SessionPool::used() const
{
Poco::Mutex::ScopedLock lock(_mutex);
return (int) _activeSessions.size();
}
int SessionPool::idle() const
{
Poco::Mutex::ScopedLock lock(_mutex);
return (int) _idleSessions.size();
}
int SessionPool::dead()
{
Poco::Mutex::ScopedLock lock(_mutex);
int count = 0;
SessionList::iterator it = _activeSessions.begin();
SessionList::iterator itEnd = _activeSessions.end();
for (; it != itEnd; ++it)
{
if (!(*it)->session()->isConnected())
++count;
}
return count;
}
int SessionPool::allocated() const
{
Poco::Mutex::ScopedLock lock(_mutex);
return _nSessions;
}
int SessionPool::available() const
{
if (_shutdown) return 0;
return _maxSessions - used();
}
void SessionPool::setFeature(const std::string& name, bool state)
{
Poco::Mutex::ScopedLock lock(_mutex);
if (_shutdown) throw InvalidAccessException("Session pool has been shut down.");
if (_nSessions > 0)
throw InvalidAccessException("Features can not be set after the first session was created.");
_featureMap.insert(FeatureMap::ValueType(name, state));
}
bool SessionPool::getFeature(const std::string& name)
{
FeatureMap::ConstIterator it = _featureMap.find(name);
if (_shutdown) throw InvalidAccessException("Session pool has been shut down.");
if (_featureMap.end() == it)
throw NotFoundException("Feature not found:" + name);
return it->second;
}
void SessionPool::setProperty(const std::string& name, const Poco::Any& value)
{
Poco::Mutex::ScopedLock lock(_mutex);
if (_shutdown) throw InvalidAccessException("Session pool has been shut down.");
if (_nSessions > 0)
throw InvalidAccessException("Properties can not be set after first session was created.");
_propertyMap.insert(PropertyMap::ValueType(name, value));
}
Poco::Any SessionPool::getProperty(const std::string& name)
{
PropertyMap::ConstIterator it = _propertyMap.find(name);
if (_propertyMap.end() == it)
throw NotFoundException("Property not found:" + name);
return it->second;
}
void SessionPool::applySettings(SessionImpl* pImpl)
{
FeatureMap::Iterator fmIt = _featureMap.begin();
FeatureMap::Iterator fmEnd = _featureMap.end();
for (; fmIt != fmEnd; ++fmIt) pImpl->setFeature(fmIt->first, fmIt->second);
PropertyMap::Iterator pmIt = _propertyMap.begin();
PropertyMap::Iterator pmEnd = _propertyMap.end();
for (; pmIt != pmEnd; ++pmIt) pImpl->setProperty(pmIt->first, pmIt->second);
}
void SessionPool::customizeSession(Session&)
{
}
void SessionPool::putBack(PooledSessionHolderPtr pHolder)
{
Poco::Mutex::ScopedLock lock(_mutex);
if (_shutdown) return;
SessionList::iterator it = std::find(_activeSessions.begin(), _activeSessions.end(), pHolder);
if (it != _activeSessions.end())
{
if (pHolder->session()->isConnected())
{
// reverse settings applied at acquisition time, if any
AddPropertyMap::iterator pIt = _addPropertyMap.find(pHolder->session());
if (pIt != _addPropertyMap.end())
pHolder->session()->setProperty(pIt->second.first, pIt->second.second);
AddFeatureMap::iterator fIt = _addFeatureMap.find(pHolder->session());
if (fIt != _addFeatureMap.end())
pHolder->session()->setFeature(fIt->second.first, fIt->second.second);
// re-apply the default pool settings
applySettings(pHolder->session());
pHolder->access();
_idleSessions.push_front(pHolder);
}
else --_nSessions;
_activeSessions.erase(it);
}
else
{
poco_bugcheck_msg("Unknown session passed to SessionPool::putBack()");
}
}
void SessionPool::onJanitorTimer(Poco::Timer&)
{
Poco::Mutex::ScopedLock lock(_mutex);
if (_shutdown) return;
SessionList::iterator it = _idleSessions.begin();
while (_nSessions > _minSessions && it != _idleSessions.end())
{
if ((*it)->idle() > _idleTime || !(*it)->session()->isConnected())
{
try { (*it)->session()->close(); }
catch (...) { }
it = _idleSessions.erase(it);
--_nSessions;
}
else ++it;
}
}
void SessionPool::shutdown()
{
Poco::Mutex::ScopedLock lock(_mutex);
if (_shutdown) return;
_shutdown = true;
_janitorTimer.stop();
closeAll(_idleSessions);
closeAll(_activeSessions);
}
void SessionPool::closeAll(SessionList& sessionList)
{
SessionList::iterator it = sessionList.begin();
for (; it != sessionList.end();)
{
try { (*it)->session()->close(); }
catch (...) { }
it = sessionList.erase(it);
if (_nSessions > 0) --_nSessions;
}
}
} } // namespace Poco::Data
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