validate验证

/*
<br> * Generated by MyEclipse Struts
<br> * Template path: templates/java/JavaClass.vtl
<br> */
<br>package com.Propmanager.struts.form;
<br>
<br>import javax.servlet.http.HttpServletRequest;
<br>import org.apache.struts.action.ActionErrors;
<br>import org.apache.struts.action.ActionForm;
<br>import org.apache.struts.action.ActionMapping;
<br>import org.apache.struts.action.ActionMessage;
<br>import org.apache.struts.action.ActionMessages;
<br>/**
<br> * MyEclipse Struts
<br> * Creation date: 04-06-2008
<br> *
<br> * XDoclet definition:
<br> * @struts.form name="loadUserCheckForm"
<br> */
<br>public class LoadCheckForm extends ActionForm {
<br>
<br> public String  username=null;
<br> public String userpassword=null;
<br> public void setUsername()
<br> {
<br>  this.username=username;
<br>  System.out.println(username);
<br>  
<br> }
<br> public void setUserpassword()
<br> {
<br>  this.userpassword=userpassword;
<br> }
<br> public String getUsername()
<br> {
<br>  return (this.username);
<br> }
<br> public String getUserpassword()
<br> {
<br>  return (this.userpassword);
<br> }
<br>
<br> public void reset(ActionMapping mapping, HttpServletRequest request) {
<br>        this.username=null;
<br>        this.userpassword=null;
<br>  }
<br> public ActionErrors validate(ActionMapping mapping,
<br>   HttpServletRequest request) {
<br>  
<br>  ActionErrors errors=new ActionErrors();
<br>  if((username==null)==true)
<br>   errors.add( "username" ,new ActionMessage("error UserName"));
<br>  System.out.println(username);
<br>  if((userpassword==null))
<br>   errors.add("userpassword",new ActionMessage("error UserPassword"));
<br>  return errors;
<br> }
<br>}
<br>请问一下为什么获取不到表单提交的用户名和密码，我这只是一个简单的验证用户密码是否为空，有谁帮我看看吗？小弟在此谢过，正在关注中

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