Reading Specific Text from a JTextField

Question

Hello I am currently trying to create a computer game\program and the main thing that it uses is input from the user, commands, in a JTextField. So I already have a basic text field set up called "question" (JTextField question = new JTextField(15);) in a JFrame and an OK button to enter the text. Next is a String "answer". This is: String answer = question.getText().toUpperCase();

This is how the field is set up. Net is the 3 if statements that give an error if no text is entered, if it is not the right word, and of course, the correct answer. They are as follows:

Public class ButtonListener extends ActionListener
{
     publix void actionPerformed(ActionEvent e)
     {
          if(e.getSource() == buttonOK)
          {
           String answer = question.getText().toUpperCase();

          if(answer.length() == 0)
          {
               JOptionPane.showMessageDialog(
                    Window.this,
                    "ERROR: NO INPUT",
                    "ERROR",
                    JOptionPane.INFORMATION_MESSAGE);
          }

          if(answer == "XENIX")
          {
               JOptionPane.showMessageDialog(
                    Window.this,
                    "Welcome, Sir",
                    "Greetings",
                    JOptionPane.INFORMATION_MESSAGE);
          }

          if(answer != "XENIX" && answer.length > 0)
          {
               JOptionPane.showMessageDialog(
                    Window.this,
                    "ERROR: INCORECT PASSWORD",
                    "ERROR",
                    JOptionPane.INFORMATION_MESSAGE);
          }

This is how the if statements react when text is entered and the ok button is pressed. Everything works but when I type in "Xenix", it says "ERROR: INCORRECT PASSWORD". The, "Welcome, Sir" message never shows, even though using a print method it shows it is clearly getting "XENIX" from the answer. Why is it not working? Is there another method I'm supposed to use? Please respond soon! Thanks!

Answer 1

if(question.getText() !=null && !question.getText().isEmpty())
{
    String answer = question.getText().toUpperCase();

    if(answer.length() == 0)
    {
        ------------------
        ------------------
    }   

    if(answer.equals("XENIX"))
    {
        ------------------
        ------------------
    }

    if((!answer.equals("XENIX")) && answer.length > 0)
    {
        ------------------
        ------------------
    }
}