JDBC工具类实现登陆验证-Java(新手)

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JDBC工具类：

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 package cn.chuang.JdbcDome;

 import java.sql.*;

 public class JdbcUtilss {
     private static final String user = "root";
     private static final String r = "root";
     private static final String p = "root";
     private static final String url = "jdbc:mysql:///semployee";
     private static final String DRIVER = "com.mysql.jdbc.Driver";
     //注册驱动。
     static{
         try {
             Class.forName(DRIVER);
         } catch (ClassNotFoundException e) {
             e.printStackTrace();
         }
     }
     //得到数据库链接。
     public static Connection getConnection() throws Exception {
         return DriverManager.getConnection(url,r,p);
     }

     //关闭链接，执行打开的资源。
     public static void close(Connection conn,Statement stmt){
         if (stmt!=null){
             try {
                 stmt.close();
             } catch (Exception e) {
                 e.printStackTrace();
             }
         }
         if (conn!=null){
             try {
                 conn.close();
             } catch (Exception e) {
                 e.printStackTrace();
             }
         }
     }
     //关闭所有打开的资源。
     public static void close(Connection conn, Statement stmt, ResultSet rs){
         if (stmt!=null){
             try {
                 stmt.close();
             } catch (Exception e) {
                 e.printStackTrace();
             }
         }if (conn!=null){
             try {
                 conn.close();
             } catch (Exception e) {
                 e.printStackTrace();
             }
         }
         if (rs!=null){
             try {
                 rs.close();
             } catch (Exception e) {
                 e.printStackTrace();
             }
         }
     }

 }

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利用JDBC工具类实现登陆验证：

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 package cn.chuang.JdbcDome;

 import java.sql.Connection;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.Statement;
 import java.util.Scanner;

 public class JdbcUtilsUser {
     public static void main(String[] args){
         Scanner sc = new Scanner(System.in);
         System.out.println("请输入用户名");
         String name = sc.nextLine();

         System.out.println("请您输入密码");
         String password = sc.nextLine();
         login(name,password);
     }
     public static void login(String name,String password){
         Connection conn = null;
         PreparedStatement pre=null;
         ResultSet rs = null;

         try {
             conn = JdbcUtilss.getConnection();
             String sql = "select * from zh where uname = '"+name+"' and upd = '"+password+"'" ;
             pre = conn.prepareStatement(sql);
             rs = pre.executeQuery();
             System.out.println(sql);
             if (rs.next()){
                 System.out.println("登陆成功，欢迎您"+name);
             }else{
                 System.out.println("登录失败");
             }
         } catch (Exception e) {
             e.printStackTrace();
         }
         finally {
             JdbcUtilss.close(conn,pre,rs);
         }
     }
 }