用struts,
在视图上有一个用户名和密码的输入框,和提交按钮,
我的LogonContentForm.java里已经写了相应的程序,
但是为什么我运行时,什么也不输,还是出现这个错误
HTTP Status 500 -
--------------------------------------------------------------------------------
type Exception report
message
description The server encountered an internal error () that prevented it from fulfilling this request.
exception
java.lang.NullPointerException
org.apache.struts.tiles.xmlDefinition.FactorySet.getDefinition(FactorySet.java:156)
org.apache.struts.tiles.definition.ComponentDefinitionsFactoryWrapper.getDefinition(ComponentDefinitionsFactoryWrapper.java:124)
org.apache.struts.tiles.TilesRequestProcessor.processTilesDefinition(TilesRequestProcessor.java:180)
org.apache.struts.tiles.TilesRequestProcessor.internalModuleRelativeForward(TilesRequestProcessor.java:341)
org.apache.struts.action.RequestProcessor.processValidate(RequestProcessor.java:980)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:255)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1482)
org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:525)
javax.servlet.http.HttpServlet.service(HttpServlet.java:709)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
note The full stack trace of the root cause is available in the Apache Tomcat/5.0.28 logs.
--------------------------------------------------------------------------------
Apache Tomcat/5.0.28
_____________________________LogonContentForm.java程序
package com.yourcompany.struts.form;
//import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.*;
import org.apache.struts.action.*;
//import org.apache.struts.action.ActionErrors;
//import org.apache.struts.action.ActionForm;
//import org.apache.struts.action.ActionMapping;
public class LogonContentForm extends ActionForm {
private String userName;
private String userPassword;
public ActionErrors validate(
ActionMapping mapping,
HttpServletRequest request) {
ActionErrors errors=new ActionErrors();
if(userName==""||userName.length()<1)
errors.add("userName",new ActionError("addressbook.logo.no.username.error"));
return errors;
}
public void reset(ActionMapping mapping, HttpServletRequest request) {
this.userName=null;
// TODO Auto-generated method stub
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getUserPassword() {
return userPassword;
