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);
        }
    }
}