javaweb增删查改mysql_JavaWebJDBC+MySql通讯录实现简单的增删改查功能案例详解

摘要&＃xff1a;这篇Java开发技术栏目下的“JavaWeb JDBC &＃43; MySql 通讯录实现简单的增删改查功能案例详解”&＃xff0c;介绍的技术点是“javaweb、MySQL、增删改查、JDBC、增删改、通讯录”&＃xff0c;希望对大家开发技术学习和问题解决有帮助。

本文实例讲述了JavaWeb JDBC &＃43; 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&＃xff0c;具体如下&＃xff1a;

开发工具&＃xff1a;Eclipse &＃43; Navicat

一、新建项目

在Eclipse中新建一个Web项目&＃xff0c;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&＃xff0c;项目的目录如下

最终实现的效果如下所示&＃xff1a;

点击新增可以进行联系人的新增&＃xff0c;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&＃xff1a;在测试数据库连接时&＃xff0c;需要注意mysql 时区的设置&＃xff0c;安装mysql时默认的时区时美国时间&＃xff0c;与本地相差8个小时&＃xff0c;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 &＃61; "com.mysql.jdbc.Driver";

public static final String URL &＃61; "jdbc:mysql://localhost:3306/demo?rewriteBatchedStatements&＃61;true&useUnicode&＃61;true&characterEncoding&＃61;utf8&allowMultiQueries&＃61;true&serverTimezone&＃61;GMT%2B8";

public static final String USER &＃61; "root";

public static final String PASSWORD &＃61; "sasa";

Connection conn &＃61; null;

PreparedStatement pstmt &＃61; null;

ResultSet rs &＃61; null;

public void getConnection() {

try {

// 加载数据库驱动

Class.forName(DRIVER);

// 获得数据库连接

conn &＃61; DriverManager.getConnection(URL, USER, PASSWORD);

}

catch (ClassNotFoundException e) {

e.printStackTrace();

}

catch (SQLException e) {

e.printStackTrace();

}

}

public int executeUpdate(String sql, Object... obj) {

int num &＃61; 0;

getConnection();

try {

PreparedStatement pstmt &＃61; conn.prepareStatement(sql);

for (int i &＃61; 0; i

pstmt.setObject(i &＃43; 1, obj[i]);

}

num &＃61; pstmt.executeUpdate();

} catch (SQLException e) {

e.printStackTrace();

} finally {

closeAll();

}

return num;

}

public ResultSet executeQuery(String sql, Object... obj) {

getConnection();

try {

PreparedStatement pstmt &＃61; conn.prepareStatement(sql);

for (int i &＃61; 0; i

pstmt.setObject(i &＃43; 1, obj[i]);

}

rs &＃61; 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&＃xff1a;

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 &＃61; id;

this.name &＃61; name;

this.age &＃61; age;

this.phone &＃61; phone;

this.date &＃61; date;

this.favorite &＃61; 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 &＃61; id;

}

public String getName() {

return name;

}

public void setName(String name) {

this.name &＃61; name;

}

public int getAge() {

return age;

}

public void setAge(int age) {

this.age &＃61; age;

}

public String getPhone() {

return phone;

}

public void setPhone(String phone) {

this.phone &＃61; phone;

}

public Date getDate() {

return date;

}

public void setDate(Date date) {

this.date &＃61; date;

}

public String getFavorite() {

return favorite;

}

public void setFavorite(String favorite) {

this.favorite &＃61; favorite;

}

}

增删改查的实现&＃xff1a;

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 &＃61; null;

public List GetAllContact(){

List list &＃61; new ArrayList();

String sql &＃61; "select * from contact";

rs &＃61; executeQuery(sql);

try {

while (rs.next()) {

Contact f &＃61; 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 &＃61; 0;

String sql &＃61; "insert into contact(name,age,phone,date,favorite) values(?,?,?,?,?)";

try {

num &＃61; 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 &＃61; 0;

String sql &＃61; "delete from contact where id &＃61; ?";

try {

num &＃61; executeUpdate(sql, id);

}

catch(Exception ex) {

ex.printStackTrace();

}

return num;

}

public Contact GetContact(int id) {

String sql &＃61; "select * from contact where id &＃61; ?";

Contact contact &＃61; null;

rs &＃61; executeQuery(sql, id);

try {

while(rs.next()) {

contact &＃61; 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 &＃61; 0;

String sql &＃61; "update contact set name &＃61; ?,age &＃61; ?,phone &＃61; ?,date &＃61; ?,favorite &＃61; ? where id &＃61; ?";

try {

num &＃61; 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

*/

&＃64;WebServlet("/ContactServlet")

public class ContactServlet extends HttpServlet {

private static final long serialVersionUID &＃61; 1L;

/**

* &＃64;see HttpServlet#HttpServlet()

*/

public ContactServlet() {

super();

// TODO Auto-generated constructor stub

}

/**

* &＃64;see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)

*/

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

doPost(request,response);

}

/**

* &＃64;see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)

*/

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

response.setContentType("text/html;charset&＃61;utf-8");

request.setCharacterEncoding("utf-8");

HttpSession session &＃61; request.getSession();

PrintWriter out &＃61; response.getWriter();

ContactService ud &＃61; new ContactService();

// 获得do属性

String dos &＃61; request.getParameter("do");

if (dos &＃61;&＃61; null || dos.equals("")) {

dos &＃61; "index";

}

// 主页

if (dos.equals("index")) {

List ulist &＃61; ud.GetAllContact();

request.setAttribute("ulist", ulist);

request.getRequestDispatcher("/index.jsp").forward(request, response);

return;

}

if(dos.equals("add")) {

String name &＃61; request.getParameter("name");

int age &＃61; Integer.parseInt(request.getParameter("age"));

String phone &＃61; request.getParameter("phone");

String dates &＃61; request.getParameter("date");

SimpleDateFormat sdf &＃61; new SimpleDateFormat("yy-MM-dd");

Date date &＃61; null;

try {

date &＃61; (Date)sdf.parse(dates);

} catch (ParseException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

//爱好获取

String favorite &＃61; request.getParameter("favorite");

Contact contact &＃61; new Contact(0,name,age,phone,date,favorite);

ud.AddContact(contact);

out.print("");

}

if(dos.equals("del")) {

String ids &＃61; request.getParameter("id");

int id &＃61; Integer.parseInt(ids);

ud.DeleteContact(id);

out.print("");

}

if(dos.equals("editbefore")) {

int id &＃61; Integer.parseInt(request.getParameter("id"));

Contact f &＃61; ud.GetContact(id);

session.setAttribute("edituser", f);

response.sendRedirect("edit.jsp");

return;

}

if(dos.equals("edit")) {

try {

int id &＃61; Integer.parseInt(request.getParameter("id"));

String name &＃61; request.getParameter("name");

int age &＃61; Integer.parseInt(request.getParameter("age"));

String phone &＃61; request.getParameter("phone");

String dates &＃61; request.getParameter("date");

SimpleDateFormat sdf &＃61; new SimpleDateFormat("yy-MM-dd");

Date date &＃61; null;

date &＃61; (Date)sdf.parse(dates);

String favorite &＃61; request.getParameter("favorite");

Contact contact &＃61; new Contact(id,name,age,phone,date,favorite);

ud.UpdateContact(contact);

out.print("");

}

catch(ParseException ex) {

ex.printStackTrace();

}

}

}

}

JSP页面

index 页面&＃xff0c;此页面需要添加 jstl.jar 和standard.jar &＃xff0c;否则无法引用 taglib

String path &＃61; request.getContextPath();

String basePath &＃61; request.getScheme() &＃43; "://"

&＃43; request.getServerName() &＃43; ":" &＃43; request.getServerPort()

&＃43; path &＃43; "/";

//下面的语句初始为初始化页面&＃xff0c;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 &＃61; new ContactService();

List ulist &＃61; ud.GetAllContact();

request.setAttribute("ulist", ulist);

%>

href&＃61;"https://cdn.bootcss.com/foundation/5.5.3/css/foundation.min.css" rel&＃61;"external nofollow" rel&＃61;"external nofollow" rel&＃61;"external nofollow" >

table {

margin: auto;

}

td {

text-align: center;

}

h1 {

margin-left: 40%;

}

a#add {

margin-left: 45%;

}

新增小伙伴

序号姓名年龄电话生日爱好操作${U.id}${U.name}${U.age}${U.phone}${U.date}${U.favorite}修改 删除

标签遍历List--%>

Add页面

String path &＃61; request.getContextPath();

String basePath &＃61; request.getScheme() &＃43; "://"

&＃43; request.getServerName() &＃43; ":" &＃43; request.getServerPort()

&＃43; path &＃43; "/";

%>

href&＃61;"https://cdn.bootcss.com/foundation/5.5.3/css/foundation.min.css" rel&＃61;"external nofollow" rel&＃61;"external nofollow" rel&＃61;"external nofollow" >

姓名

年龄

电话

生日

爱好

Edit页面

String path &＃61; request.getContextPath();

String basePath &＃61; request.getScheme() &＃43; "://"

&＃43; request.getServerName() &＃43; ":" &＃43; request.getServerPort()

&＃43; path &＃43; "/";

%>

href&＃61;"https://cdn.bootcss.com/foundation/5.5.3/css/foundation.min.css" rel&＃61;"external nofollow" rel&＃61;"external nofollow" rel&＃61;"external nofollow" >

姓名

年龄

电话

生日

爱好

希望本文所述对大家java程序设计有所帮助。