AWT-EventQueue-0" StackOverflowError

Question

Afternoon all, i have a problem with some JFrame code, this JFrame is started when the user presses "New User", and whenever they do so, i get:

Exception in thread "AWT-EventQueue-0" java.lang.StackOverflowError
at frontend.Registration.<init>(Registration.java:36)
at frontend.Registration.<init>(Registration.java:25)
at frontend.Registration.<init>(Registration.java:25)
at frontend.Registration.<init>(Registration.java:25)

With this code:

package frontend;

import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.sql.SQLException;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.border.EmptyBorder;

public class Registration extends JFrame {

/**
 * 
 */
private static final long serialVersionUID = 1L;

private static boolean ranOnce = false;

private JPanel contentPane;
private Registration reg = new Registration();
private JTextField userTF;
private JTextField passTF;
private JTextField emailTF;

private LoginProcess lp = new LoginProcess();
private JLabel error;

/**
 * Create the frame.
 */
public Registration() {
    if (!ranOnce) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    ranOnce = true;
                    reg = new Registration();
                    reg.setVisible(true);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setBounds(100, 100, 245, 195);
    setLocationRelativeTo(null);
    contentPane = new JPanel();
    contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
    setContentPane(contentPane);
    contentPane.setLayout(null);

    JLabel lblUsername = new JLabel("Username:");
    lblUsername.setBounds(10, 11, 75, 14);
    contentPane.add(lblUsername);

    JLabel lblPassword = new JLabel("Password:");
    lblPassword.setBounds(10, 36, 75, 14);
    contentPane.add(lblPassword);

    JLabel lblEmail = new JLabel("Email:");
    lblEmail.setBounds(10, 61, 75, 14);
    contentPane.add(lblEmail);

    userTF = new JTextField();
    userTF.setBounds(95, 8, 130, 20);
    contentPane.add(userTF);
    userTF.setColumns(10);

    passTF = new JTextField();
    passTF.setColumns(10);
    passTF.setBounds(95, 33, 130, 20);
    contentPane.add(passTF);

    emailTF = new JTextField();
    emailTF.setColumns(10);
    emailTF.setBounds(95, 58, 130, 20);
    contentPane.add(emailTF);

    error = new JLabel("Error: Username already in use");
    error.setBounds(10, 120, 215, 14);
    contentPane.add(error);

    JButton regBtn = new JButton("Register");
    regBtn.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent arg0) {
            try {
                if (lp.newUser(userTF.getText(), passTF.getText(), emailTF.getText())) {
                    reg.setVisible(false);
                    Main.mainFrame.setVisible(true);
                } else {
                    if (lp.duplicateAccount) {
                        error.setText("lol");
                    }
                }
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    });
    regBtn.setBounds(10, 86, 215, 23);
    contentPane.add(regBtn);


}
}

I know this error is caused by an infinite loop, or something. but i have a boolean in place to stop it from infinitely running. This code was working about 20mins ago, and i haven't changed the first part of the constructor since i created the code.

Any ideas? Thanks..

1) Java GUIs have to work on different OS', screen size, screen resolution etc. As such, they are not conducive to pixel perfect layout. Instead use layout managers, or [combinations of them](http://stackoverflow.com/a/5630271/418556) along with layout padding and borders for [white space](http://stackoverflow.com/a/17874718/418556). 2) See [The Use of Multiple JFrames, Good/Bad Practice?](http://stackoverflow.com/q/9554636/418556) — Andrew Thompson, Sep 24 '14 at 06:13

score 3 · Accepted Answer · answered Sep 24 '14 at 05:52

3

You create a new Object in the line private Registration reg = new Registration();.

You should create this object in the consturctor.

answered Sep 24 '14 at 05:52

Jens

67,715
15
98
113

score 1 · Answer 2 · answered Sep 24 '14 at 05:51

1

The problem at that line:

private Registration reg = new Registration();

You get in a infinite loop and then stack overflow.

answered Sep 24 '14 at 05:51

DiogoSantana

2,404
2
19
24

AWT-EventQueue-0" StackOverflowError

2 Answers2