javaweb基本增删改查实现

package dao;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

import entry.user;
import util.DBUtil;

public class userDao {
    //
        public boolean add(user user) {
            String sql = "insert into user2(id,name,password,sex,no,mail,address,class1,yuan,sheng,bei) "
                    + "values('" + user.getId() + "','"  + user.getName() + "','"  + user.getPassword() + "','"  + user.getSex() + "','"  + user.getNo() + "','"  + user.getMail() + "','"  + user.getAddress() + user.getClass1() + "','"  + user.getYuan() +  "','"  + user.getSheng()+ "','"  + user.getBei()+"','"+"')";
            //
            Connection conn = DBUtil.getConn();
            Statement state = null;
            boolean f = false;
            int a = 0;
            
            try {
                state = conn.createStatement();
                state.executeUpdate(sql);
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                //
                DBUtil.close(state, conn);
            }
            
            if (a > 0) {
                f = true;
            }
            return f;
        }
        
        
        
        public boolean id(String id) {
            boolean f = false;
            String sql = "select id from user2 where name = '" + id + "'";
            //
            Connection conn = DBUtil.getConn();
            Statement state = null;
            ResultSet rs = null;       
            try {
                state = conn.createStatement();
                rs = state.executeQuery(sql);
                while (rs.next()) {
                    f = true;
                }
            } catch (SQLException e) {
                e.printStackTrace();
            } finally {
                DBUtil.close(rs, state, conn);
            }
            return f;
        }
}
package entry;

public class user {
private String id;
private String password;
private String name;
private String sex;
private String address;
private String no;
private String mail;
private String class1;
private String yuan;
private String sheng;
private String bei;

public String getId() {
    return id;
}
public void setId(String id) {
    this.id = id;
}
public String getPassword() {
    return password;
}
public void setPassword(String password) {
    this.password = password;
}
public String getName() {
    return name;
}
public void setName(String name) {
    this.name = name;
}
public String getClass1() {
    return class1;
}
public void setClass1(String class1) {
    this.class1 = class1;
}
public String getYuan() {
    return yuan;
}
public void setYuan(String yuan) {
    this.yuan = yuan;
}
public String getSheng() {
    return sheng;
}
public void setSheng(String sheng) {
    this.sheng = sheng;
}
public String getBei() {
    return bei;
}
public void setBei(String bei) {
    this.bei = bei;
}
public String getSex() {
    return sex;
}
public void setSex(String sex) {
    this.sex = sex;
}
public String getAddress() {
    return address;
}
public void setAddress(String address) {
    this.address = address;
}
public String getNo() {
    return no;
}
public void setNo(String no) {
    this.no = no;
}
public String getMail() {
    return mail;
}
public void setMail(String mail) {
    this.mail = mail;
}
public user(){}
public user(String name, String password) {
    this.name = name;
    this.password = password;
};
public user(String id, String password, String name, String sex, String address, String no, String mail,String class1,String yuan,String sheng,String bei) {
    super();
    this.id = id;
    this.password = password;
    this.name = name;
    this.sex = sex;
    this.address = address;
    this.no = no;
    this.mail = mail;
    this.class1 = class1;
    this.yuan = yuan;
    this.sheng = sheng;
    this.bei = bei;
}
}

package service;

import dao.userDao;
import entry.user;

public class userservice {
userDao cDao = new userDao();
    
    /*添加*/
    public boolean add(user user) {
        boolean f = false;
        if(!cDao.id(user.getId())) {
            cDao.add(user);
            f = true;
        }
        return f;
    }
    
    
    
}
package 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 entry.user;
import service.userservice;

/**
 * Servlet implementation class AddServlet
 */
@WebServlet("/AddServlet")
public class AddServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public AddServlet() {
        super();
        // TODO Auto-generated constructor stub
    }
    
        
        userservice service = new userservice();    
        protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
            req.setCharacterEncoding("utf-8");
            String method = req.getParameter("method");
            if("add".equals(method))
             add(req,resp);
        
        }
        
        
        protected void add(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
             request.setCharacterEncoding("utf-8");
                //鑾峰彇鏁版嵁
                String id = request.getParameter("id");
                String password = request.getParameter("password");
                String name = request.getParameter("name");
                String sex = request.getParameter("sex");
                String address = request.getParameter("address");
                String no = request.getParameter("no");
                String mail = request.getParameter("mail");
                String class1 = request.getParameter("class1");
                String yuan = request.getParameter("yuan");
                String sheng = request.getParameter("sheng");
                String bei = request.getParameter("bei");
                user user = new user(id,password,name,sex,address,no,mail,class1,yuan,sheng,bei);
                 System.out.println(id);
                //娣诲姞鍚庢秷鎭樉绀�
                if(service.add(user)) {
                    request.setAttribute("message", "添加成功");
                    request.getRequestDispatcher("NewFile.jsp").forward(request,response);
                } else {
                    request.setAttribute("message", "添加失败");
                    request.getRequestDispatcher("NewFile.jsp").forward(request,response);
                }
        }

        protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

            doGet(request, response);
        }

    


    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        response.getWriter().append("Served at: ").append(request.getContextPath());
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */


}
package util;
 
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
 
/*
 * 鏁版嵁搴撹繛鎺ュ伐鍏�
 */
public class DBUtil {
     
    public static String db_url = "jdbc:mysql://localhost:3306/user?useSSL=false";
    public static String db_user = "root";
    public static String db_pass = "root";
     
    public static Connection getConn () {
        Connection conn = null;
         
        try {
            Class.forName("com.mysql.jdbc.Driver");//鍔犺浇椹卞姩
            conn = DriverManager.getConnection(db_url, db_user, db_pass);
        } catch (Exception e) {
            e.printStackTrace();
        }
         
        return conn;
    }
     
    /*10鍏抽棴杩炴帴*/
    public static void close (Statement state, Connection conn) {
        if (state != null) {
            try {
                state.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
         
        if (conn != null) {
            try {
                conn.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
     
    public static void close (ResultSet rs, Statement state, Connection conn) {
        if (rs != null) {
            try {
                rs.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
         
        if (state != null) {
            try {
                state.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
         
        if (conn != null) {
            try {
                conn.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
 
    public static void main(String[] args) throws SQLException {
        Connection conn = getConn();
        PreparedStatement pstmt = null;
        ResultSet rs = null;
        String sql ="select * from user";
        pstmt = conn.prepareStatement(sql);
        rs = pstmt.executeQuery();
        if(rs.next()){
            System.out.println("绌�");
        }else{
            System.out.println("涓嶇┖");
        }
    }
}

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<title>Insert title here</title>
<meta charset="UTF-8">
    <title>注册页面</title>
</head>
<body>
    <%
         Object message = request.getAttribute("message");
         if(message!=null && !"".equals(message)){
     
    %>
         <script type="text/javascript">
              alert("<%=request.getAttribute("message")%>");
         </script>
    <%} %>
    <div align="center">
        <h6 style="color: black;">当前位置：添加学生信息</h6>
     
        <form name = "form1" action="${pageContext.request.contextPath}/AddServlet?method=add" method="post" onsubmit="return check_submit()">
    <table>
            <tr>
                <td>登陆账号</td>
                <td colspan="2"> <input type="text" id="id" name="id"  maxlength="12" onblur="blur_id()" onfocus="focus_id()"/></td>
                <td width="300"><div id="result"></td>
            </tr>
            <tr>
                <td>登陆密码</td>
                <td colspan="2"> <input type="password" id="password" name="password" onblur="blur_pass()" onfocus="focus_pass()" /></td>
                <td width="300"><div id="result1"></td>
            </tr>
            <tr>
                <td>姓名</td>
                <td colspan="2"><input type="text" id="name" name="name" /></td>
            </tr>
            <tr>
                <td>性别：</td>
                <td colspan="2">
              <select name="sex"id="sex" >
              <option value="男" >男</option>
              <option value="女" >女</option>
              
            </select></td>
            </tr><tr>
                <td>入学年份：</td>
                <td colspan="2">
              <select name="address"id="address" >
              <option value="1998" >1998</option>
              <option value="1999" >1999</option>
              <option value="2000" >2000</option>
            </select></td>
            </tr><tr>
                <td>学号:2018</td>
                <td colspan="2"><input  maxlength="4" type="tel" id="no" name="no" /></td>
                 <td width="300"><div id="result_name"></td>
            </tr><tr>
                <td>邮箱</td>
                <td colspan="2"><input type="email" id="mail" name="mail" ></td>
            </tr>
            <tr>
                <td>所在班级</td>
                <td colspan="2"><input type="text" id="class1" name="class1" /></td>
                 
            </tr>
            <tr>
                <td>所在院校</td>
                <td colspan="2"><input type="text" id="yuan" name="yuan" /></td>
                 
            </tr>
            <tr>
                <td>生源地</td>
                <td colspan="2"><input type="text" id="sheng" name="sheng" /></td>
                 
            </tr>
            <tr>
                <td>备注</td>
                <td colspan="2"><input type="text" id="bei" name="bei" /></td>
                 
            </tr>
            <tr>
            <td colspan="3"> <button type="submit" class="b">保&nbsp;&nbsp;&nbsp;存</button>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
                <button type="reset" class="b">重&nbsp;&nbsp;&nbsp;置</button></td>
            
            </tr>
    </table>
    </form>
    </div>
    <script type="text/javascript">
/*
    表单验证
*/
var flag = false;   // flag 如果为true（即用户名合法）就允许表单提交， 如果为false（即用户名不合法）阻止提交
function focus_pass()
{
    var nameObj = document.getElementById("result1");
    nameObj.innerHTML = "由六位字符和数字组成";
    nameObj.style.color="#999";
    }
function blur_pass()
{
    var nameObj = document.getElementById("result1");
    // 判断用户名是否合法
    var str2 = check_user_pass(document.form1.password.value);
    nameObj.style.color="red";
    if ("密码合法" ==  str2)
    {
        flag = true;
        nameObj.innerHTML = str2;
    }
    else
    {
        nameObj.innerHTML = str2;
    }
}

function check_user_pass(str)
{  var str2 = "密码合法";
if ("" == str)
{
    str2 = "密码为空";
    return str2;
}
else if (str.length!=6)
{
    str2 = "用户名应是六位组成";
    return str2;
}
else if (!check_word(str))
{
    str2 = "未含有英文字符";
    return str2;
}

return str2;
    
    
    }





function focus_id()
{
    var nameObj = document.getElementById("result");
    nameObj.innerHTML = "由六到十二英文字符和数字组成";
    nameObj.style.color="#999";
    }
function blur_id()
{
    var nameObj = document.getElementById("result");
    // 判断用户名是否合法
    var str2 = check_user_id(document.form1.id.value);
    nameObj.style.color="red";
    if ("用户名合法" ==  str2)
    {
        flag = true;
        nameObj.innerHTML = str2;
    }
    else
    {
        nameObj.innerHTML = str2;
    }
}

function check_user_id(str)
{
    var str2 = "用户名合法";
    if ("" == str)
    {
        str2 = "用户名号为空";
        return str2;
    }
    else if ((str.length<=4)||(str.length>=12))
    {
        str2 = "用户名应是六到十二位组成";
        return str2;
    }
    else if (!check_word(str))
    {
        str2 = "未含有英文字符";
        return str2;
    }
    else if(!check_firstword(str))
    {
        str2 = "必须以英文字母开头";
        return str2;
    }
    return str2;
}


function check_firstword(str)
{   var arr = ["a", "b", "c", "d", "e", "f", "g", "h","i","j", "k", "l", "m", "n", "o", "p", "q","r", "s", "t", "u", "v", "w", "x", "y","z","A", "B", "C", "D", "E", "F", "G", "H","I","J", "K", "L", "M", "N", "O", "P", "Q","R","S", "T", "U", "V", "W", "X", "Y", "Z"];
for (var i = 0; i < arr.length; i++)
{
        if (arr[i] == str.charAt(0))
        {
            return true;
        }
}   
return false;
    }


function check_word(str)
{   var arr = ["a", "b", "c", "d", "e", "f", "g", "h","i","j", "k", "l", "m", "n", "o", "p", "q","r", "s", "t", "u", "v", "w", "x", "y","z","A", "B", "C", "D", "E", "F", "G", "H","I","J", "K", "L", "M", "N", "O", "P", "Q","R","S", "T", "U", "V", "W", "X", "Y", "Z"];
for (var i = 0; i < arr.length; i++)
{
    for (var j = 0; j < str.length; j++)
    {
        if (arr[i] == str.charAt(j))
        {
            return true;
        }
    }
}   
return false;
    }

// 验证用户名是否含有特殊字符
function check_other_char(str)
{
    var arr = ["&", "\\", "/", "*", ">", "<", "@", "!"];
    for (var i = 0; i < arr.length; i++)
    {
        for (var j = 0; j < str.length; j++)
        {
            if (arr[i] == str.charAt(j))
            {
                return true;
            }
        }
    }   
    return false;
}
// 根据验证结果确认是否提交
function check_submit()
{
    if (flag == false)
    {
        return false;
    }
    return true;
}
</script>
</head>
</body>