[孩子在車上‧Babyincar's Blog]

In some cases
當client尚未發出http request給
com.opensymphony.webwork.dispatcher.ServletDispatcher之前
webwork似乎尚未initial
因此操作ServletActionContext裡的方法經常有null之類的錯誤

例如我們會採用listener在web ap server start時
將property載入並set進application
再寫個SECSystemUtil class 提供static方法來存取application中的property

static {
logger = Logger.getLogger("sec");

context = ServletActionContext.getServletContext();
login_prop = (Properties) context.getAttribute("login_pram");
system_prop = (Properties) context.getAttribute("system_pram");
}
但假如在webwork尚未initial前，用servlet or jsp去call SECSystemUtil
則ServletActionContext.getServletContext()會產生錯誤

所以要在call SECSystemUtil 前先set一些東東 (see sec project RateQuery)

public class RateQuery extends HttpServlet{
public void init(ServletConfig config){

ServletActionContext.setServletContext(config.getServletContext());
....
}
}

或是在jsp中(see myskype top.inc)

com.opensymphony.webwork.ServletActionContext.setRequest(request);