JSPMVC模式登陆注册系统

「已注销」 2019-06-12 12:55:12

关于JSP用MVC模式设计登陆注册系统的，我照书上写的代码一直报错，我也不懂
package myservlet.control;
import mybean.data.*;
import java.sql.*;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.util.*;
public class HandleLogin extends HttpServlet{
public void init(ServletConfig config) throws ServletException{
super.init(config);
try{
Class.forName("com.mysql.jdbc.Driver");
}
catch(Exception e){}
}
public String handleString(String s){
try{ byte bb[]=s.getBytes("iso-8859-1");
s=new String(bb);
}
catch(Exception ee){}
return s;
}
public void doPost(HttpServletRequest request,HttpServletResponse response)throws ServletException,IOException{
Connection con;
Statement sql;
Login loginBean=null;
String backNews="";
HttpSession session=request.getSession(true);
try{
loginBean=(Login)session.getAttribute("login");
if(loginBean==null){
loginBean=new Login();
session.setAttribute("login",loginBean);
}
}
catch(Exception ee){
loginBean=new Login();
session.setAttribute("login",loginBean);
}
String logname=request.getParameter("logname").trim();
String password=request.getParameter("password").trim();
boolean ok=loginBean.getSuccess();
logname=handleString(logname);
password=handleString(password);
if(ok==true&&logname.equals(loginBean.getLogname())){
backNews=logname+"已经登陆过了";
loginBean.setBackNews(backNews);
}
else{
String uri="jdbc:mysql://127.0.0.1/teachingsystem";
boolean boo=(logname.length()>0)&&(password.length()>0);
try{
con=DriverManager.getConnection(uri,"root","123456");
String condition="select * from member where logname = '"+logname+"' and password ='"+password+"'";
sql=con.createStatement();
if(boo){
ResultSet rs=sql.executeQuery(condition);
boolean m=rs.next();
if(m==true){
backNews="登录成功";
loginBean.setBackNews(backNews);
loginBean.setSuccess(true);
loginBean.setLogname(logname);
}
else{
backNews="您输入的用户名不存在，或密码不般配";
loginBean.setBackNews(backNews);
loginBean.setSuccess(false);
loginBean.setLogname(logname);
loginBean.setPassword(password);
}
}
else{
backNews="您输入的用户名不存在，或密码不般配";
loginBean.setBackNews(backNews);
loginBean.setSuccess(false);
loginBean.setLogname(logname);
loginBean.setPassword(password);
}
con.close();
}
catch(SQLException exp){
backNews=""+exp;
loginBean.setBackNews(backNews);
loginBean.setSuccess(false);
}
}
RequestDispatcher dispatcher=request.getRequestDispatcher("showloginmess.jsp");//转发
dispatcher.forward(request,response);
}
public void doGet(HttpServletRequest request,HttpServletResponse response)throws ServletException,IOException{
doPost(request,response);
}
}

报错如下
java.lang.NoSuchMethodError: javax.servlet.http.HttpServletRequest.getHttpServletMapping()Ljavax/servlet/http/HttpServletMapping;
myservlet.control.HandleLogin.doPost(HandleLogin.java:89)
javax.servlet.http.HttpServlet.service(HttpServlet.java:661)
javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)

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