Question

I have a properties file that holds username and password which I use in my java program however I am not being able to store more than one username and password like I do in database and just select where username and password match the many rows in the database. I imagine I need to have a two-dimensional array stored in the file holding usernames and corresponding passwords but I’ve failed to figure out how to do it and neither has google given me a way to hold a two-dimensional array in a file yet. Here are the key/value pairs for my username and password in the file

    `password=k
     username=k`

And here is the code that reads them and compares with what the user inserts

   `String usr = userfield.getText();
    String pwd = new String(pwdfield.getPassword());
    Properties config = new Properties();
    InputStream is;

    try {

        is = new FileInputStream("config.properties");
        config.load(is);

        if (usr.toString().equals(config.getProperty("user").toString()) && pwd.toString().equals(config.getProperty("pass").toString())) {
            new DocMenu();
            lgFrame.dispose();

        } else {
            JOptionPane.showMessageDialog(lgFrame, "Wrong credentials try again", "Oops", JOptionPane.ERROR_MESSAGE);

        }

        is.close();

    } catch (Exception ex) {
        System.out.println(ex);
        ex.printStackTrace();
    }`

Could someone please tell me how to change the properties file and the code so that I am able to have multiple usernames and passwords in the file to grant access to any user as long as their username and password exist.

Answer 1

If you store the property name as a concatenation of some key with the username, and the password as the value like this;

#Some bad passwords
username.bob=password
username.scott=tiger
username.admin=admin

..then you can check like this;

String password = config.getProperty("username." + usr.toString());
if (password != null && password.equals(pwd.toString())) {
  new DocMenu();
  lgFrame.dispose();
} else {
  JOptionPane.showMessageDialog(lgFrame, "Wrong credentials try again", "Oops", JOptionPane.ERROR_MESSAGE);
}