/**
* 工厂方法，产生日志数据聚合类。
*
* @param string $identifier
* @param boolean $throwException
* @throws ZtChart_Model_Monitor_Aggregate_Exception
* @return ZtChart_Model_Monitor_Aggregate_Abstract
*/
public static function factory($identifier, $throwException = true)
{
if (null === self::$_loader) {
self::$_loader = new Zend_Loader_PluginLoader(array('ZtChart_Model_Monitor_Aggregate_' => realpath(__DIR__ . '/Aggregate')));
}
$identifier = implode('_', array_map('ucfirst', explode('_', $identifier)));
if (false === ($aggregateClass = self::$_loader->load($identifier, false))) {
if (!$throwException) {
return false;
}
throw new ZtChart_Model_Monitor_Aggregate_Exception("Specified aggregate class '{$identifier}' could not be found");
}
return new $aggregateClass();
}
/**
* 取得日志数据聚合分析的对象
*
* @param string $identifier
* @return false|ZtChart_Model_Monitor_Aggregate_Abstract
*/
public function getAggregate($identifier)
{
if (!array_key_exists($identifier, $this->_aggregates)) {
try {
$this->_aggregates[$identifier] = ZtChart_Model_Monitor_Aggregate::factory($identifier);
} catch (ZtChart_Model_Monitor_Aggregate_Exception $e) {
return false;
}
}
return $this->_aggregates[$identifier];
}