final public static function getInstance() {
	
		if (NULL == self::$instance) {
			self::$instance = new self();
			self::$instance->startChrono();
		}
		
		return self::$instance;
	
	}
final public static function getInstance() {
	
		if (NULL == self::$instance) {
			self::$instance = new self();
			self::$instance->startChrono();
		}
		
		return self::$instance;
	
	}
final public static function getInstance ( ) { if ( NULL == self :: $ instance ) { self :: $ instance = new self ( ) ; self :: $ instance -> startChrono ( ) ; } return self :: $ instance ; }
Singleton instance method.

@return	Logger
Singleton instance method .