JavaWeb JDBC + MySql 通讯录实现简单的增删改查功能案例详解

发布时间：2020-10-14 07:26:25 作者：sun_jinhang
来源：脚本之家阅读：351

本文实例讲述了JavaWeb JDBC + MySql 通讯录实现简单的增删改查功能。分享给大家供大家参考，具体如下：

开发工具：Eclipse + Navicat

项目源码：Github:https://github.com/Sunjinhang/JavaWeb

一、新建项目

在Eclipse中新建一个Web项目，至于如何新建Web项目以及如何添加Tomcat服务器的就不赘述了，项目的目录如下

JavaWeb JDBC + MySql 通讯录实现简单的增删改查功能案例详解

最终实现的效果如下所示：

JavaWeb JDBC + MySql 通讯录实现简单的增删改查功能案例详解

点击新增可以进行联系人的新增，点击修改/删除可以进行联系人的修改和删除

部分代码如下

数据库连接：在测试数据库连接时，需要注意mysql 时区的设置，安装mysql时默认的时区时美国时间，与本地相差8个小时，所以如果不修改则在链接数据库时会报错。

package pers.contact.dao;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
public class BaseDao {
    private static final String DRIVER = "com.mysql.jdbc.Driver";
    public static final String URL = "jdbc:mysql://localhost:3306/demo?rewriteBatchedStatements=true&useUnicode=true&characterEncoding=utf8&allowMultiQueries=true&serverTimezone=GMT%2B8";
    public static final String USER = "root";
    public static final String PASSWORD = "sasa";
    Connection conn = null;
    PreparedStatement pstmt = null;
    ResultSet rs = null;
    public void getConnection() {
        try {
            // 加载数据库驱动
            Class.forName(DRIVER);
            // 获得数据库连接
            conn = DriverManager.getConnection(URL, USER, PASSWORD);
        }
        catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
        catch (SQLException e) {
            e.printStackTrace();
        }
    }
    public int executeUpdate(String sql, Object... obj) {
        int num = 0;
        getConnection();
        try {
            PreparedStatement pstmt = conn.prepareStatement(sql);
            for (int i = 0; i < obj.length; i++) {
                pstmt.setObject(i + 1, obj[i]);
            }
            num = pstmt.executeUpdate();
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            closeAll();
        }
        return num;
    }
    public ResultSet executeQuery(String sql, Object... obj) {
        getConnection();
        try {
            PreparedStatement pstmt = conn.prepareStatement(sql);
            for (int i = 0; i < obj.length; i++) {
                pstmt.setObject(i + 1, obj[i]);
            }
            rs = pstmt.executeQuery();
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return rs;
    }
    public void closeAll() {
        try {
            rs.close();
        } catch (SQLException e) {
            e.printStackTrace();
        }
        try {
            pstmt.close();
        } catch (SQLException e) {
            e.printStackTrace();
        }
        try {
            conn.close();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

联系人：

package pers.contact.entity;
import java.util.Date;
public class Contact {
    public Contact(int id, String name, int age, String phone, Date date, String favorite) {
        super();
        this.id = id;
        this.name = name;
        this.age = age;
        this.phone = phone;
        this.date = date;
        this.favorite = favorite;
    }
    private int id;
    private String name;
    private int age;
    private String phone;
    private Date date;
    private String favorite;
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
    public String getPhone() {
        return phone;
    }
    public void setPhone(String phone) {
        this.phone = phone;
    }
    public Date getDate() {
        return date;
    }
    public void setDate(Date date) {
        this.date = date;
    }
    public String getFavorite() {
        return favorite;
    }
    public void setFavorite(String favorite) {
        this.favorite = favorite;
    }
}

增删改查的实现：

package pers.contact.service;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import pers.contact.entity.Contact;
import pers.contact.dao.BaseDao;;
public class ContactService extends BaseDao {
    ResultSet rs = null;
    public List<Contact> GetAllContact(){
        List<Contact> list = new ArrayList();
        String sql = "select * from contact";
        rs = executeQuery(sql);
        try {
            while (rs.next()) {
                Contact f = new Contact(rs.getInt(1), rs.getString(2),
                        rs.getInt(3), rs.getString(4), rs.getDate(5),
                        rs.getString(6));
                list.add(f);
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return list;
    }
    public int AddContact(Contact contact)
    {
        int num = 0;
        String sql = "insert into contact(name,age,phone,date,favorite) values(?,?,?,?,?)";
        try {
            num = executeUpdate(sql, contact.getName(), contact.getAge(), contact.getPhone(),
                    contact.getDate(), contact.getFavorite());
        } catch (Exception e) {
            e.printStackTrace();
        }
        return num;
    }
    public int DeleteContact(int id)
    {
        int num = 0;
        String sql = "delete from contact where id = ?";
        try {
            num = executeUpdate(sql, id);
        }
        catch(Exception ex) {
            ex.printStackTrace();
        }
        return num;
    }
    public Contact GetContact(int id) {
        String sql = "select * from contact where id = ?";
        Contact contact = null;
        rs = executeQuery(sql, id);
        try {
            while(rs.next()) {
                contact = new Contact(rs.getInt(1),rs.getString(2),rs.getInt(3),rs.getString(4),rs.getDate(5),rs.getString(6));
            }
        }
        catch(SQLException ex){
            ex.printStackTrace();
        }
        return contact;
    }
    public int UpdateContact(Contact contact) {
        int num = 0;
        String sql = "update contact set name = ?,age = ?,phone = ?,date = ?,favorite = ? where id = ?";
        try {
            num = executeUpdate(sql, contact.getName(),contact.getAge(),contact.getPhone(),contact.getDate(),contact.getFavorite(),contact.getId());
        }
        catch(Exception ex) {
            ex.printStackTrace();
        }
        return num;
    }
}

Servlet:

package pers.contact.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
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 javax.servlet.http.HttpSession;
import pers.contact.entity.Contact;
import pers.contact.service.ContactService;
/**
 * Servlet implementation class ContactServlet
 */
@WebServlet("/ContactServlet")
public class ContactServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;
  /**
   * @see HttpServlet#HttpServlet()
   */
  public ContactServlet() {
    super();
    // TODO Auto-generated constructor stub
  }
    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doPost(request,response);
    }
    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        response.setContentType("text/html;charset=utf-8");
        request.setCharacterEncoding("utf-8");
        HttpSession session = request.getSession();
        PrintWriter out = response.getWriter();
        ContactService ud = new ContactService();
        // 获得do属性
        String dos = request.getParameter("do");
        if (dos == null || dos.equals("")) {
            dos = "index";
        }
        // 主页
        if (dos.equals("index")) {
            List<Contact> ulist = ud.GetAllContact();
            request.setAttribute("ulist", ulist);
            request.getRequestDispatcher("/index.jsp").forward(request, response);
            return;
        }
        if(dos.equals("add")) {
            String name = request.getParameter("name");
            int age = Integer.parseInt(request.getParameter("age"));
            String phone = request.getParameter("phone");
            String dates = request.getParameter("date");
            SimpleDateFormat sdf = new SimpleDateFormat("yy-MM-dd");
            Date date = null;
            try {
                date = (Date)sdf.parse(dates);
            } catch (ParseException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            //爱好获取
            String favorite = request.getParameter("favorite");
            Contact contact = new Contact(0,name,age,phone,date,favorite);
            ud.AddContact(contact);
            out.print("<script>alert('新增成功！');window.location='ContactServlet?do=index';</script>");
        }
        if(dos.equals("del")) {
            String ids = request.getParameter("id");
            int id = Integer.parseInt(ids);
            ud.DeleteContact(id);
            out.print("<script>alert('删除成功！');window.location='ContactServlet?do=index';</script>");
        }
        if(dos.equals("editbefore")) {
            int id = Integer.parseInt(request.getParameter("id"));
            Contact f = ud.GetContact(id);
            session.setAttribute("edituser", f);
            response.sendRedirect("edit.jsp");
            return;
        }
        if(dos.equals("edit")) {
            try {
                int id = Integer.parseInt(request.getParameter("id"));
                String name = request.getParameter("name");
                int age = Integer.parseInt(request.getParameter("age"));
                String phone = request.getParameter("phone");
                String dates = request.getParameter("date");
                SimpleDateFormat sdf = new SimpleDateFormat("yy-MM-dd");
                Date date = null;
                date = (Date)sdf.parse(dates);
                String favorite = request.getParameter("favorite");
                Contact contact = new Contact(id,name,age,phone,date,favorite);
                ud.UpdateContact(contact);
                out.print("<script>alert('修改成功！');window.location='ContactServlet?do=index';</script>");
            }
            catch(ParseException ex) {
                ex.printStackTrace();
            }
        }
    }
}

JSP页面

index 页面，此页面需要添加 jstl.jar 和standard.jar ，否则无法引用 taglib

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ page import="pers.contact.entity.Contact"%>
<%@ page import="pers.contact.service.ContactService"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<%
    String path = request.getContextPath();
    String basePath = request.getScheme() + "://"
            + request.getServerName() + ":" + request.getServerPort()
            + path + "/";
    //下面的语句初始为初始化页面，如果不加下面语句访问主页不会显示数据库中保存的数据
    ContactService ud = new ContactService();
    List<Contact> ulist = ud.GetAllContact();
    request.setAttribute("ulist", ulist);
%>
<!DOCTYPE html>
<html>
<head>
<base href="<%=basePath%>" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
<meta charset="ISO-8859-1">
<link rel="stylesheet"
    href="https://cdn.bootcss.com/foundation/5.5.3/css/foundation.min.css" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
<script src="https://cdn.bootcss.com/jquery/2.1.1/jquery.min.js"></script>
<script
    src="https://cdn.bootcss.com/foundation/5.5.3/js/foundation.min.js"></script>
<script
    src="https://cdn.bootcss.com/foundation/5.5.3/js/vendor/modernizr.js"></script>
<style type="text/css">
table {
    margin: auto;
}
td {
    text-align: center;
}
h2 {
    margin-left: 40%;
}
a#add {
    margin-left: 45%;
}
</style>
<title>Insert title here</title>
</head>
<body >
    <h2>通讯录主页</h2>
    <a id="add" href="add.jsp" rel="external nofollow" >新增小伙伴</a>
    <table>
        <thead>
            <tr>
                <th>序号</th>
                <th>姓名</th>
                <th>年龄</th>
                <th>电话</th>
                <th>生日</th>
                <th>爱好</th>
                <th>操作</th>
            </tr>
            <c:forEach var="U" items="${ulist}">
            <tr>
                <th>${U.id}</th>
                <th>${U.name}</th>
                <th>${U.age}</th>
                <th>${U.phone}</th>
                <th>${U.date}</th>
                <th>${U.favorite}</th>
                <th><a href="ContactServlet?do=editbefore&id=${U.id}" rel="external nofollow" >修改</a> <a href="ContactServlet?do=del&id=${U.id}" rel="external nofollow" >删除</a> </th>
            </tr>
            </c:forEach>
        </thead>
        <%--<c:forEach/>标签遍历List--%>
    </table>
</body>
</html>

Add页面

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
    String path = request.getContextPath();
    String basePath = request.getScheme() + "://"
            + request.getServerName() + ":" + request.getServerPort()
            + path + "/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
<title>My JSP 'add.jsp' starting page</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet"
    href="https://cdn.bootcss.com/foundation/5.5.3/css/foundation.min.css" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
<script src="https://cdn.bootcss.com/jquery/2.1.1/jquery.min.js"></script>
<script
    src="https://cdn.bootcss.com/foundation/5.5.3/js/foundation.min.js"></script>
<script
    src="https://cdn.bootcss.com/foundation/5.5.3/js/vendor/modernizr.js"></script>
</head>
<body>
    <h2>新增页面</h2>
<form action="ContactServlet?do=add" method="post" >
  <fieldset>
  <label>姓名 <input type="text" placeholder="name" required="required" name="name" /> </label>
  <label>年龄 <input type="number" placeholder="age" required="required" min="1" max="133" name="age" /> </label>
  <label>电话<input type="text" placeholder="phonenum" required="required" name="phone" /> </label>
  <label>生日<input type="date" placeholder="date" required="required" name="date" /> </label>
  <label>爱好<input type="text" placeholder="favorite" required="required" name="favorite" /> </label>
  <input type="submit" value="新增" class="button" />
  <input type="reset" class="button" />
  </fieldset>
 </form>
</body>
</html>

Edit页面

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
    String path = request.getContextPath();
    String basePath = request.getScheme() + "://"
            + request.getServerName() + ":" + request.getServerPort()
            + path + "/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
<title>My JSP 'add.jsp' starting page</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet"
    href="https://cdn.bootcss.com/foundation/5.5.3/css/foundation.min.css" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
<script src="https://cdn.bootcss.com/jquery/2.1.1/jquery.min.js"></script>
<script
    src="https://cdn.bootcss.com/foundation/5.5.3/js/foundation.min.js"></script>
<script
    src="https://cdn.bootcss.com/foundation/5.5.3/js/vendor/modernizr.js"></script>
</head>
<body>
    <h2>修改页面</h2>
    <form action="ContactServlet?do=edit&id=${edituser.id}" method="post" >
        <fieldset>
            <label>姓名 <input type="text" placeholder="name" name="name" value = "${edituser.name}">
            </label>
            <label>年龄 <input type="text" placeholder="age" name="age" value = "${edituser.age}">
            </label>
            <label>电话<input type="text" placeholder="phone" name="phone" value = "${edituser.phone}">
            </label>
            <label>生日<input type="date" placeholder="date" name="date" value = "${edituser.date}">
            </label>
            <label>爱好<input type="text" placeholder="favorite" name="favorite" value = "${edituser.favorite}">
            </label>
            <input type="submit" value="修改" class="button"> <input type="reset" class="button">
        </fieldset>
    </form>
</body>
</html>

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JavaWeb JDBC + MySql 通讯录实现简单的增删改查功能案例详解

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