如何通过JDBC连接使用IO

Question

this is my method for writing db query.

        public static void post() throws Exception{

        int clientMPNumber = Parcel.typeClientNumber();
        int orderPassword = Parcel.generatePass();

        try{
            Connection con = ConnectionDB.getConnection();
            PreparedStatement posted = con.prepareStatement("UPDATE `BankDB`.`Info` SET `Money`='77777' WHERE `ClientID`='77' AND `ClientPass`='1111';");

            posted.executeUpdate();
        }catch(Exception e){System.out.println(e);}
    finally{    
        System.out.println("Insert completed");
    }
    }

I'm trying to do something like ATM machine. So I expect that user types his ID and password, and then the user can withdraw money or deposit money. So I want to check login data correctness. User needs to type correct ID/password [logins/passwords are placed in MySQL DB].

PreparedStatement posted = con.prepareStatement("UPDATE `BankDB`.`Info` SET `Money`='77777' WHERE `ClientID`='USER TYPES IT' AND `ClientPass`='USER TYPES IT';");

There is a sentence: "USER TYPES IT", this is my problem. I want to use here a Scanner or something like this. How can I do it?

Answer 1

A prototype for you (just an example, you should split up the part get userid, password, outside of this function for better practice):

public void post (){
    Scanner sc = new Scanner(System.in);
    System.out.println ("please enter user id:");
    String userId = sc.nextLine();
    System.out.println("please enter password:");
    String pass = sc.nextLine();
    Connection con;
    PreparedStatement posted;
    try {
        con = ConnectionDB.getConnection();
        String sql = "UPDATE `BankDB`.`Info` SET `Money`='77777' WHERE `ClientID`=? AND `ClientPass`=?";
        posted = con.prepareStatement(sql);
        posted.setString(1, userId);
        posted.setString(2, pass);
        posted.executeUpdate();
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        posted.close();
        con.close();
    }
}