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copied!<p>I'm trying to get the string input from the user and store it in a file but an error comes out saying: I don't know what the issue is, it doesn't pop up as an error until I actually run the code. I just want the input from the user stored in a file that is made</p> <pre><code>Exception in thread "main" java.lang.NullPointerException at BingoHelper.<init>(BingoHelper.java:53) at BINGO.main(BINGO.java:8) </code></pre> <p>Main Class Code: </p> <pre><code>import javax.swing.*; import java.io.*; public class BINGO { public static void main(String[] args) throws IOException{ JLabel bg = new JLabel(); //JButton b = new JButton("Click to enter name"); BingoHelper EnterFaze = new BingoHelper(); EnterFaze.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); EnterFaze.setSize(500,500); EnterFaze.setVisible(true); EnterFaze.setLocationRelativeTo(null); EnterFaze.setLayout(null); EnterFaze.add(bg); } } </code></pre> <p>Second Class</p> <pre><code>import javax.swing.*; import java.awt.*; import java.awt.event.*; import java.io.*; public class BingoHelper extends JFrame implements WindowListener, ActionListener{ JTextField text = new JTextField(); JLabel bg = new JLabel(); private JButton b; { b = new JButton("Click to enter name"); } JPanel pnlButton = new JPanel(); public static String fn; public static String sn; public void actionPerformed (ActionEvent e) { //BingoHelper.fn; //BingoHelper.sn; fn = JOptionPane.showInputDialog("What is your first name?"); sn = JOptionPane.showInputDialog("What is your second name(Optional)"); //JOptionPane.showMessageDialog(null, "Welcome " + fn + " " + sn + ".", "", JOptionPane.INFORMATION_MESSAGE); text.setText("Welcome " + fn + " " + sn + "."); b.setVisible(false); text.setVisible(true); text.setBounds(140,0,220,20); text.setHorizontalAlignment(JLabel.CENTER); text.setEditable(false); text.setBackground(Color.YELLOW); } public BingoHelper() throws IOException{ super("BINGO"); add(text); text.setVisible(false); add(b); this.add(pnlButton); pnlButton.setBackground(Color.BLUE); //pnlButton.add(b);+ b.setVisible(true); b.setBounds(145,145,145,20); //b.setPreferredSize(new Dimension(150,40)); b.addActionListener(this); b.setBackground(Color.GREEN); rootPane.setDefaultButton(b); File f = new File("test.txt"); String nameToWrite = fn; OutputStream outStream = new FileOutputStream(f); outStream.write(nameToWrite.getBytes()); outStream.close(); } public void windowClosing(WindowEvent e) { dispose(); System.exit(0); } public void windowOpened(WindowEvent e) {} public void windowActivated(WindowEvent e) {} public void windowIconified(WindowEvent e) {} public void windowDeiconified(WindowEvent e) {} public void windowDeactivated(WindowEvent e) {} public void windowClosed(WindowEvent e) {} </code></pre> <p>}</p>

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