/**
 * Constructor
 *
 * @param   string  $writeprefix  Prefix of the stream (optional). Unlike the JPATH_*, this has a final path separator!
 * @param   string  $readprefix   The read prefix (optional).
 * @param   array   $context      The context options (optional).
 *
 * @since   1.7.0
 */
public function __construct($writeprefix = '', $readprefix = '', $context = array())
{
    $this->writeprefix = $writeprefix;
    $this->readprefix = $readprefix;
    $this->contextOptions = $context;
    $this->_buildContext();
}