Question

I am writing a login script for a game that i have made. I am currently in the process of checking the information given to make sure it is valid. I have run into the problem that when I go to check to see if 2 text fields have the same value. When they do they do the opposite of what i want it to do.

private void regAccConfEmailFieldFocusFocusLost(FocusEvent event) {
    if(regAccConfEmailField.getText() == regAccEmail.getText() && regAccConfEmail != null)
    {
        regAccConfEmailField.setBorder(new LineBorder(Color.green, 1, false));
        confEmail = true;
    }
    else
    {
        regAccConfEmailField.setBorder(new LineBorder(Color.red, 1, false));
        confEmail = false;
    }
}

private void regAccConfSecQFieldFocusFocusLost(FocusEvent event) {
    if(regAccConfSecQField.getText() == null)
    {
        regAccConfSecQField.setBorder(new LineBorder(Color.red, 1, false));
        secQuestion = false;
    }
    else
    {
        regAccConfSecQField.setBorder(new LineBorder(Color.green, 1, false));
        secQuestion = true;
    }
}  

This is the code that i have, and i need to know why each of these methods does the opposite of what it is given.

Say that regAccConfEmailField and regAccEmailField both equal [e-mail]
It will go to the if statement and not the else. If needed, i can provide more code.

Answer 1

There are 2 issues with this statement:

if (regAccConfEmailField.getText() == regAccEmail.getText() && regAccConfEmail != null)

• You should have the null check first so that it short-circuits the expression if regAccConfEmail is null
• Also use String.equals to compare String content instead of the == operator. The == operator is used to compare object references and is currently giving you the opposite of what you want as the values from the 2 fields will be different String objects.

You can replace with

if (regAccConfEmail != null && regAccConfEmailField.getText().equals(regAccEmail.getText()))

• Also regAccConfSecQField.getText() can never be null from a JTextField so replace

  if (regAccConfSecQField.getText() == null)

with

  if (regAccConfSecQField.getText().trim().isEmpty())

• Finally, you appear to be using a FocusListener which relys on FocusEvents for performing the validation. Have a look at using an DocumentListener for triggering validation on document changes.