我这里有一个servlet 文件叫做LoginServlet  但他不能在myeclipse里面编译成功
总是报错java.lang.NoClassDefFoundError: control
Exception in thread "main" 
请问应该怎么修改呀
他的代码是
package com.wxpn.tutorial.servlet;import java.io.IOException;
import java.util.Collection;import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;import com.wxpn.tutorial.control.news.MasterMgr;
public class LoginServlet extends javax.servlet.http.HttpServlet implements
javax.servlet.Servlet {public LoginServlet() {
super();
}
protected void doPost(HttpServletRequest request,
HttpServletResponse response) throws ServletException,
                                      IOException {
response.setContentType("text/html;charset=UTF-8");// 获取提交的用户名:
String strUserName = request.getParameter("username");
// 获取提交的密码:
String strPassword = request.getParameter("password");
MasterMgr masterMgr = new MasterMgr();
if (masterMgr.checkLogin(strUserName, strPassword)) {
// 登录成功时,把strUserName设成session变量UserName
request.getSession(true).setAttribute("username", strUserName);
request.getSession(true).setAttribute("password", strPassword);
masterMgr.addloginnum(strUserName);response.sendRedirect("admin/main.jsp");
} else {
response.sendRedirect("admin/loginerror.jsp");
}}