public static function getInstance($userAgent = null, $accept = null)
	{
		$signature = serialize(array($userAgent, $accept));

		if (empty(self::$instances[$signature]))
		{
			self::$instances[$signature] = new self($userAgent, $accept);
		}

		return self::$instances[$signature];
	}
public static function getInstance($userAgent = null, $accept = null)
	{
		$signature = serialize(array($userAgent, $accept));

		if (empty(self::$instances[$signature]))
		{
			self::$instances[$signature] = new self($userAgent, $accept);
		}

		return self::$instances[$signature];
	}
public static function getInstance ( $ userAgent = null , $ accept = null ) { $ signature = serialize ( array ( $ userAgent , $ accept ) ) ; if ( empty ( self :: $ instances [ $ signature ] ) ) { self :: $ instances [ $ signature ] = new self ( $ userAgent , $ accept ) ; } return self :: $ instances [ $ signature ] ; }
Returns the global Browser object, only creating it
if it doesn't already exist.

@param   string  $userAgent  The browser string to parse.
@param   string  $accept     The HTTP_ACCEPT settings to use.
@return  object  The Browser object.
Returns the global Browser object only creating it if it doesn t already exist .