Struts問題

[cheong]

public ActionForward execute(ActionMapping mapping,
Actionform form,
HttpServletRequest request,
HttpServletResponse response)
throws IOException, ServletException {
String action = request.getParameter("action");
Logonform logonform = (Logonform) form;
String userLanguage = logonform.getLanguage();
String account = logonform.getAccount();

在ActionForward execute中, 為什麼是可以使用getLanguage(); 和getAccount();等 get的方法, 因為我不見有setLanguage(); 等set方法, 沒有 set 為何可以 get 到值 ???