河北金力集团公文流转系统

package com.Util;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Scanner;
import org.apache.catalina.User;

public class DBUtil {
public static final String connectionURL="jdbc:mysql://localhost:3306/new_schem1?useUnicode=true&characterEncoding=GB18030&useSSL=false&serverTimezone=GMT&allowPublicKeyRetrieval=true";
public static final String username="root";
public static final String password="123456";
static Connection connection;
static ResultSet rSet;
static PreparedStatement ps;
static Scanner scanner=new Scanner(System.in);

public static Connection getConnection()
{
  try {
   Class.forName("com.mysql.cj.jdbc.Driver");
   //Class.forName("com.mysql.cj.jdbc.Driver");
   return DriverManager.getConnection(connectionURL, username, password);
  } catch (Exception e) {
   // TODO: handle exception
   System.out.println("数据库连接失败");
   e.printStackTrace();
  }
  return null;
} //数据库连接

public static boolean getUsername()     //遍历获取数据库中的内容
{
  try {
   Connection connection2 = getConnection();
   connection=connection2;
      ps= connection.prepareStatement("select * from new_schem1.jinliwenjian");
   rSet=ps.executeQuery();//执行sql语句
   //System.out.println("yhjyuki");
   while(rSet.next())
   {
     System.out.println(rSet.getString(1)+" "+rSet.getString(2)+" "+rSet.getString(3)+" "+rSet.getString(4)+" "+rSet.getString(5)+" "+rSet.getString(6));
   }
  }
  catch(SQLException e)
  {
   e.printStackTrace();
  }
  return false;
}

public static boolean dengluchaxun(bean.User user)
{

  try {
       connection=getConnection();
       String sql="select * from jinliwenjian where username = '"+user.getUsername()+"' and password = '"+user.getPassword()+"' and status != 0";
       ps= connection.prepareStatement(sql);
       rSet=ps.executeQuery();
       if(rSet.next()==false)
        {
        System.out.println("用户名或密码错误");
        return false;
        }
       else
        {
        System.out.println("用户名及密码正确");
        return true;
        }
  } catch (Exception e) {
   // TODO: handle exception
  }
  return false;

}

public static void main(String[] args) {
  // TODO 自动生成的方法存根
  getUsername();


}

}

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>金立文件流转系统（办公室）</title>
<script>
function check()
   {

     var username=document.getElementById("text1").value;
        var n=/^[a-zA-Z0-9_]{4,10}$/;
        if(!n.test(username)){
       document.getElementById("pwspan1").innerHTML="请输入正确的用户名!";
       }else{
         document.getElementById("pwspan1").innerHTML="";
       }
       }
    function check1()
    {
        var password1=document.getElementById("text2").value;
        var n=/^[a-zA-Z0-9_]{4,10}$/;
        if(!n.test(password1)){
       document.getElementById("pwspan2").innerHTML="请输入正确的密码!";
       }else{
         document.getElementById("pwspan2").innerHTML="";
       }

      }
     </script>
</head>
<body>
   <style>
   .div1{
    background-color:lightseagreen;
                1000px;
                height:100px;
                margin:auto;
                padding-top:50px;
                font-family: "微软雅黑";
                font-size:40px;
   }
   .div2{
    background: yellow;
    500px;
    height:250px;
    margin: auto;
    padding-top:80px;
   }
   .div3{
    background-color:yellow;
    300px;
    height:170px;
   }
   .div4{

    color:red;
   }
  </style>
<form action="Servlet?n=downland" method="post">
     <div class="div1"><center><b>河北金力集团公文流转系统</b></center></div>
<div class="div2">
  <center>
  <div class="div3">
  <h7>用户名:</h7><input type="text" maxlength="20" id="username" name="username" onblur ="check()" />
  <div class="div4" id="pwspan1"></div><br/>
  <center><h7>   密码:</h7><input type="password" maxlength="15" id="password" name="password" onblur="check1()">
  <div class="div4" id="pwspan2"></div><br>
  <a href="#"><br/><center> <input name="submit" type="submit" class="btn_grey" value="登录"><br><a>
  </div>
  </center>
</div>
     </form>

</body>
</html>

package com.Servlet;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.Util.DBUtil;

import bean.User;

/**
* Servlet implementation class Servlet
*/
@WebServlet("/Servlet")
public class Servlet extends HttpServlet {
private static final long serialVersionUID = 1L;

    /**
     * @see HttpServlet#HttpServlet()
     */
    public Servlet() {
        super();
        // TODO Auto-generated constructor stub
    }

/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
  // TODO Auto-generated method stub
  request.setCharacterEncoding("UTF-8");
  response.getWriter().append("Served at: ").append(request.getContextPath());
  String id=request.getParameter("id");
  String username=request.getParameter("username");
  String password=request.getParameter("password");
  String permissionid=request.getParameter("permissionid");
  String job=request.getParameter("job");
  String status=request.getParameter("status");
  User user=new User();
  if(request.getParameter("n").equals("downland"))
  {
   String username1=request.getParameter("username");
   user.setUsername(username1);
   String password1=request.getParameter("password");
   user.setPassword(password1);
   DBUtil.dengluchaxun(user);
  }




}

/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
doGet(request, response);
}

}

package bean;

public class User {
protected int id;
protected String username;
protected String password;
protected String permissionid;
protected String job;
protected int status;

public int getId() {
return id;
}

public void setId(int id) {
this.id = id;
}

public String getUsername() {
return username;
}

public void setUsername(String username) {
this.username = username;
}

public String getPassword() {
return password;
}

public void setPassword(String password) {
this.password = password;
}

public String getPermissionid() {
return permissionid;
}

public void setPermissionid(String permissionid) {
this.permissionid = permissionid;
}

public String getJob() {
return job;
}

public void setJob(String job) {
this.job = job;
}

public int getStatus() {
return status;
}

public void setStatus(int status) {
this.status = status;
}
}

原文地址：https://www.cnblogs.com/yangqqq/p/12012491.html