eclipse连接mysql数据库实现怎删改查操作实例（附带源码）

 package model;

 public class User {

     private int id;
     private String name;
     private String password;
     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 String getPassword() {
         return password;
     }
     public void setPassword(String password) {
         this.password = password;
     }

 }

 package dao;

 import java.util.List;

 import model.User;

 public interface IUser {
     public void add(User user);
     public void delete(int id);
     public void update(User user);
     public User load(int id);
     public List<User> load();
     public List<User> load(String content);
 }

 package dao;

 import java.sql.Connection;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 import java.util.ArrayList;
 import java.util.List;

 import com.sun.xml.internal.bind.v2.runtime.Name;

 import model.User;
 import util.DBUtil;
 import util.UserException;

 public class UserImp implements IUser{

     public void add(User user) {

         Connection connection=DBUtil.getConnection();

         String sql = "select count(*) from t_user where name = ?";//准备sql语句

         PreparedStatement preparedStatement = null;
         ResultSet resultSet = null;

         try {
             preparedStatement =  connection.prepareStatement(sql);
             preparedStatement.setString(1, user.getName());

             resultSet = preparedStatement.executeQuery();

             while(resultSet.next()) {
                 if (resultSet.getInt(1) > 0) {
                     throw new UserException("用户已存在") ;
                 }
             }

             String sql1 = "insert into t_user(name,password) value (?,?)";
             preparedStatement = connection.prepareStatement(sql1);
             preparedStatement.setString(1, user.getName());
             preparedStatement.setString(2, user.getPassword());
             preparedStatement.executeUpdate();
         } catch (SQLException e) {

             e.printStackTrace();
         }finally {

             DBUtil.close(resultSet);
             DBUtil.close(preparedStatement);
             DBUtil.close(connection);
         }

     }

     public void delete(int id) {
         Connection connection = DBUtil.getConnection();
         String sql = "delete from t_user where id = ?";
         PreparedStatement preparedStatement = null;

         try {
             preparedStatement = connection.prepareStatement(sql);
             preparedStatement.setInt(1, id);
             preparedStatement.executeUpdate();
         } catch (SQLException e) {

             e.printStackTrace();
         }finally {
             DBUtil.close(preparedStatement);
             DBUtil.close(connection);
         }

     }

     public void update(User user) {

         Connection connection = DBUtil.getConnection();
         //准备sql语句
         String sql = "update t_user set name = ? , password=? where id = ?";
         //创建语句传输对象
         PreparedStatement preparedStatement = null;
         try {
             preparedStatement = connection.prepareStatement(sql);
             preparedStatement.setString(1, user.getName());
             preparedStatement.setString(2, user.getPassword());
             preparedStatement.setInt(3, user.getId());
             preparedStatement.executeUpdate();
         } catch (SQLException e) {

             e.printStackTrace();
         }finally {
             DBUtil.close(preparedStatement);
             DBUtil.close(connection);
         }

     }

     public User load(int id) {
         Connection connection = DBUtil.getConnection();
         //准备sql语句
         String sql = "select * from t_user  where id = ?";
         //创建语句传输对象
         PreparedStatement preparedStatement = null;
         ResultSet resultSet = null;
         User user = null;
         try {
             preparedStatement = connection.prepareStatement(sql);

             preparedStatement.setInt(1, id);
             resultSet = preparedStatement.executeQuery();
             while(resultSet.next()) {
                 user = new User();
                 user.setId(id);
                 user.setName(resultSet.getString("name"));;
                 user.setPassword(resultSet.getString("password"));

             }
         } catch (SQLException e) {

             e.printStackTrace();
         }finally {
             DBUtil.close(resultSet);
             DBUtil.close(preparedStatement);
             DBUtil.close(connection);
         }
         return  user;
     }

     @Override
     public List<User> load() {
         Connection connection = DBUtil.getConnection();
         //准备sql语句
         String sql = "select * from t_user ";
         //创建语句传输对象
         PreparedStatement preparedStatement = null;
         ResultSet resultSet = null;
         //集合中只能放入user对象
         List<User> users = new ArrayList<User>();
         User user = null;
         try {

                 preparedStatement = connection.prepareStatement(sql);

             resultSet = preparedStatement.executeQuery();
             while(resultSet.next()) {
                 user = new User();
                 user.setId(resultSet.getInt("id"));
                 user.setName(resultSet.getString("name"));
                 user.setPassword(resultSet.getString("password"));

                 users.add(user);
             }
         } catch (SQLException e) {

             e.printStackTrace();
         }finally {
             DBUtil.close(resultSet);
             DBUtil.close(preparedStatement);
             DBUtil.close(connection);
         }
         return  users;
     }

     @Override
     public List <User> load(String content) {
         Connection connection = DBUtil.getConnection();
         //准备sql语句
         String sql = "select * from t_user ";
         //创建语句传输对象
         PreparedStatement preparedStatement = null;
         ResultSet resultSet = null;
         //集合中只能放入user对象
         List<User> users = new ArrayList<User>();
         User user = null;
         try {
             if (content == null || "".equals(content)) {
                 preparedStatement = connection.prepareStatement(sql);
             }else {
                 sql += "where name like ? ";
                 preparedStatement = connection.prepareStatement(sql);
                 preparedStatement.setString(1, "%"+ content +"%");

             }
             resultSet = preparedStatement.executeQuery();
             while(resultSet.next()) {
                 user = new User();
                 user.setId(resultSet.getInt("id"));
                 user.setName(resultSet.getString("name"));
                 user.setPassword(resultSet.getString("password"));

                 users.add(user);
             }
         } catch (SQLException e) {

             e.printStackTrace();
         }finally {
             DBUtil.close(resultSet);
             DBUtil.close(preparedStatement);
             DBUtil.close(connection);
         }
         return  users;
     }
 }

 package filter;

 import java.io.IOException;

 import javax.servlet.Filter;
 import javax.servlet.FilterChain;
 import javax.servlet.FilterConfig;
 import javax.servlet.ServletException;
 import javax.servlet.ServletRequest;
 import javax.servlet.ServletResponse;

 public class CharFilter implements Filter{
     String encoding = null;
     public void init(FilterConfig filterConfig) throws ServletException {
         encoding = filterConfig.getInitParameter("encoding");
     }

     public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
             throws IOException, ServletException {

             request.setCharacterEncoding(encoding);
             chain.doFilter(request, response);
     }

     public void destroy() {

     }
 }

 package util;

 import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;

 public class DBUtil {

         public  static  Connection getConnection() {
             /*
              * 加载驱动
              */
             try {

                 Class.forName("com.mysql.jdbc.Driver").newInstance();
             } catch (InstantiationException | IllegalAccessException | ClassNotFoundException e) {

                 e.printStackTrace();
             }
             String user = "root";
             String password = "root";
             String url = "jdbc:mysql://localhost:3306/mysql";
             /*
              * 创建连接对象
              */
             Connection connection = null;
             try {

                  connection = DriverManager.getConnection(url,user,password);
             } catch (SQLException e) {

                 e.printStackTrace();
             }
             return connection;
         }
         /*
          * 关闭资源的方法
          */

         public static void close(Connection connection) {//关闭连接对象的方法
             try {
                 if (connection != null) {
                     connection.close();
                 }

             } catch (SQLException e) {

                 e.printStackTrace();
             }
         }
         public static void close(PreparedStatement preparedStatement ) {//关闭语句传输对象的方法
             try {
                 if (preparedStatement != null) {
                     preparedStatement.close();
                 }

             } catch (SQLException e) {

                 e.printStackTrace();
             }
         }
         public static void close(ResultSet resultSet ) {//关闭结果集的方法
             try {
                 if (resultSet != null) {
                     resultSet.close();
                 }

             } catch (SQLException e) {

                 e.printStackTrace();
             }
         }

     }

 package util;

 public class UserException extends RuntimeException
 {

     public UserException() {
         super();
         // TODO Auto-generated constructor stub
     }

     public UserException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) {
         super(message, cause, enableSuppression, writableStackTrace);
         // TODO Auto-generated constructor stub
     }

     public UserException(String message, Throwable cause) {
         super(message, cause);
         // TODO Auto-generated constructor stub
     }

     public UserException(String message) {
         super(message);
         // TODO Auto-generated constructor stub
     }

     public UserException(Throwable cause) {
         super(cause);
         // TODO Auto-generated constructor stub
     }

 }

 <%@page import="com.sun.org.apache.xalan.internal.xsltc.compiler.sym"%>
 <%@page import="dao.UserImp"%>
 <%@page import="model.User"%>
 <%@ 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>
 <%
 String name=(String)request.getParameter("username");
 String password=(String)request.getParameter("pass");
 User user=new User();
 user.setName(name);
 user.setPassword(password);

 System.out.print(user.getName());
 System.out.print(user.getPassword());

 UserImp userImp=new UserImp();
 try{
 userImp.add(user);}catch(Exception e){}

 response.sendRedirect("list.jsp");
 %>

 <h2>添加成功！</h2>

 </html>

 <%@ 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>Insert title here</title>

         </head>
     <body>
         <form action="add.jsp" method="post">
             <table  border="1" bordercolor="#FFFF33" align="center" >
             <tr>

             <td align="right" colspan="2">用户名<input type="text"  name="username" style="width:100px;" /></td><br>

             </tr>
             <tr>
             <td align="right" colspan="2">密    码<input type="password"  name="pass" style="width:100px;"/></td>
             </tr>
                 <tr>
                     <td align="left" style="width:60px;height:10px;font-size:10px;">没有用户名?<a href="register.jsp">[注册]</a>一个吧</td>

                     <td align="right"><input type="submit" value="添加"style="width:100px;height:30px;font-size:16px;"/></td>

                 </tr>

             </table>

         </form>

     </body>
 </html>

 <%@page import="model.User"%>
 <%@page import="dao.UserImp"%>
 <%@ 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>Insert title here</title>
 </head>
 <%
 int id = Integer.parseInt(request.getParameter("id"));
 UserImp userImp=new UserImp();
 User user=new User();
 userImp.delete(id);
 response.sendRedirect("list.jsp");
 %>

 </html>

 <%@page import="model.User"%>
 <%@page import="java.util.List"%>
 <%@page import="dao.UserImp"%>
 <%@ 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>Insert title here</title>
 <%
     UserImp userDao = new UserImp();
     String content=request.getParameter("content");
     if(content==null||"".equals(content)){
         content="";}

         List<User> users = userDao.load(content);

 %>
 </head>
 <a href="addInput.jsp">继续添加</a>
 <body>
     <table align="center" border="1" width="500">
     <tr align="center">
         <td colspan="5" >增删改查</td>
         </tr>
     <tr>
             <form action="list.jsp" method="post">
                 <td colspan="4">
                     请输入用户名 : &nbsp;
                     <input type="text" name="content" size="40" value="<%=content%>"/> &nbsp;
                     <input type="submit" value="搜索" />
                 </td>
             </form>
         </tr>

         <tr>
             <td>用户编号</td>
             <td>用户名</td>
             <td>用户密码</td>
             <td colspan="2"> 用户操作</td>
         </tr>
         <%
             for( User user : users ){
         %>
         <tr>
             <td> <%=user.getId() %></td>
             <td> <%=user.getName()%></td>
             <td> <%=user.getPassword() %></td>

             <td> <a href="delete.jsp?id=<%=user.getId() %>" >删除</a></td>
             <td> <a href="update.jsp?id=<%=user.getId() %>" >更新</a></td>

         </tr>
         <%
             }
         %>
     </table>

 </body>

 </html>

 <%@ 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>Insert title here</title>
     </head>
 <body>
     <form action="addInput.jsp" method="post">
             <table  border="1" bordercolor="#FFFF33" align="center" >
             <tr>

             <td align="right" colspan="1">用户名<input type="text"  name="username" style="width:100px;" /></td><br>

             </tr>
             <tr>
             <td align="right" colspan="1">密    码<input type="password"  name="pass" style="width:100px;"/></td>
             </tr>
             <tr>
             <td align="right" colspan="1">确认密码<input type="password"  name="pass1" style="width:100px;"/></td>
             </tr>
             <tr>
             <td align="right" colspan="1">手机号<input type="text"  name="phone" style="width:100px;"/></td>
             </tr>
                 <tr>

                     <td align="right"><input type="submit" value="注册"style="width:100px;height:30px;font-size:16px;"/></td>

                 </tr>

             </table>

         </form>

 </body>

 </html>

 <%@page import="model.User"%>
 <%@page import="dao.UserImp"%>
 <%@ 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>Insert title here</title>
 <%
 int id = Integer.parseInt(request.getParameter("id"));
 UserImp userImp=new UserImp();
 User user=new User();
 user=userImp.load(id);
 %>
 </head>
     <body>
         <form action="update1.jsp" method="post">
             <table  border="1" bordercolor="#FFFF33" align="center" >
             <tr>
             <input type="hidden"  name="id" style="width:100px;" value="<%=user.getId()%>"/>
             <td align="right" colspan="2">用户名<input type="text"  name="username" style="width:100px;" value="<%=user.getName()%>"/></td><br>

             </tr>
             <tr>
             <td align="right" colspan="2">密    码<input type="password"  name="pass" style="width:100px;"/></td>
             </tr>
                 <tr>

                     <td align="right"><input type="submit" value="更新"style="width:100px;height:30px;font-size:16px;"/></td>

                 </tr>

             </table>

         </form>
     </body>

 </html>

<%@page import="dao.UserImp"%>
<%@page import="model.User"%>
<%@ 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>Insert title here</title>
<%
int id = Integer.parseInt(request.getParameter("id"));
String name=request.getParameter("name");
String password=request.getParameter("pass");
UserImp userImp=new UserImp();
User user=new User();
user = userImp.load(id);
//user.setName(name);
user.setPassword(password);

userImp.update(user);
response.sendRedirect("list.jsp");
%>
</head>
    <body>

    </body>
</html>