How to check if value is correct for key in HashMap in Java

Question

I'm writing a simple GUI program where I have to input login and password for user and then check if he is in database (my Hashmap). That's where i have problem. I checked if login is correct by containsKey and checked for password by containsValue. The problem is, that if in example I have 2 users:

login: user1 password: example login: user2 password: programing

If I put login as user1 in my JTextField and password "programing", the program says, that it's correct.

That's where I have a problem. How to check the password for exact login, which is key?

Would be very thankful for any clues or solutions :)

Titus · Accepted Answer · 2017-11-17 23:41:55Z

2

You can use a check like this:

 if(userEnteredPassword.equals(hashMap.get(userEnteredUsername))){ // Correct credentials. ..... }

It's important to use userEnteredPassword.equals.... instead of hashMap.get(userEnteredUsername).equals... because you'll get a null pointer exception if there is no map entry for userEnteredUsername