function ensurePropertyExists ($propName)
  {
    if (!$this->defines ($propName)) {
      throw new ComponentException(
        $this->component,
        sprintf ("Invalid property <kbd>%s</kbd> specified for a %s instance.", $propName, Debug::typeInfoOf ($this))
      );
    }
  }
function ensurePropertyExists ($propName)
  {
    if (!$this->defines ($propName)) {
      throw new ComponentException(
        $this->component,
        sprintf ("Invalid property <kbd>%s</kbd> specified for a %s instance.", $propName, Debug::typeInfoOf ($this))
      );
    }
  }
function ensurePropertyExists ( $ propName ) { if ( ! $ this -> defines ( $ propName ) ) { throw new ComponentException ( $ this -> component , sprintf ( "Invalid property <kbd>%s</kbd> specified for a %s instance." , $ propName , Debug :: typeInfoOf ( $ this ) ) ) ; } }
Throws an exception if the specified property is not available.

@param $propName
@throws ComponentException
Throws an exception if the specified property is not available .