package com.bjpowernode;

import java.sql.*;
import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;

public class JDBCTest07 {
public static void main(String[] args){

    Map<String,String> userLoginInfo = initUI();

    boolean loginSuccess=login(userLoginInfo);
    System.out.println(loginSuccess ? "登陆成功！" : "登陆失败！");

}
//用户登陆
private static boolean login(Map<String, String> userLoginInfo) {
//JDBC代码
boolean loginSuccess=false;
Connection conn=null;
PreparedStatement ps=null;
ResultSet rs=null;

    String RoomNumber=userLoginInfo.get("RoomNumber");
    String Owner1=userLoginInfo.get("Owner1");

    try {
        //1、注册驱动
        Class.forName("com.mysql.jdbc.Driver");
        //2、获取连接
        conn=DriverManager.getConnection("jdbc:mysql://rm-bp2o54v31968j69si175310nm.mysql.rds.aliyuncs.com:3306/test_db","root_db","123456");
        //3、获取预编译的数库操作对象
        String sql="SELECT * FROM tb_owner WHERE RoomNumber= ? AND Owner1= ?";
        //这里没有问题啊？？？？
        ps=conn.prepareStatement(sql);
        ps.setString(1,RoomNumber);
        ps.setString(2,Owner1);
        //4、执行SLQ
        rs=ps.executeQuery();
        if(rs.next()){
            loginSuccess=true;
        }
    } catch (Exception e) {
        e.printStackTrace();
    }finally {
        if(rs != null){
            try {
                rs.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        if(ps != null){
            try {
                ps.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        if(conn != null){
            try {
                conn.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
    return false;
}

private static Map<String, String> initUI() {
    Scanner s=new Scanner(System.in);

    System.out.print("房号：");
    String RoomNumber=s.nextLine();

    System.out.print("姓名：");
    String Owner1=s.nextLine();

    Map<String,String>userLoginInfo=new HashMap<>();
    userLoginInfo.put("RoomNumber",RoomNumber);
    userLoginInfo.put("Owner1",Owner1);
    return userLoginInfo;
}

}
用上面的法就是不行，但用以下方法是没有问题的！
//注册驱动
Class.forName("com.mysql.jdbc.Driver");
//获取连接
conn=DriverManager.getConnection("jdbc:mysql://rm-bp2o54v31968j69si175310nm.mysql.rds.aliyuncs.com:3306/test_db","root_db","123456");
//获取数据库对象
stmt=conn.createStatement();
//执行SL语句
sql = "SELECT * FROM tb_owner WHERE RoomNumber='"+RoomNumber+"' AND Owner1='"+Owner1+"'";
rs=stmt.executeQuery(sql);
//处理结果集
if(rs.next()){
loginSuccess=true;
}