title: Closing a JFrame after a button is clicked Java
body: <p>Hello I am writing a sort of Menu for an encryption program I am writing.  I finished the core of it, and now i want to try to create a GUI for it.  Here is the code for the first Menu:</p>
  
  <pre><code>package matrix_with_GUI;
  
  import javax.swing.*;
  import java.awt.event.* ;
  import java.awt.* ;
  
  public class Main_Menu extends JFrame implements ActionListener{
       private JButton action1 = new JButton ("");
       private JButton action2 = new JButton ("");
       private JPanel pane = new JPanel();
       private JLabel lbl;
  
  public static void main(String[] args) {
      Main_Menu main = new Main_Menu();
  }
  
  public Main_Menu(){
      super();
      JPanel pane=new JPanel();
      setTitle ("Start Menu") ;
      JFrame frame = new JFrame("");
  
      setVisible(true);
      setSize (380, 260) ;
      setLocation (450, 200) ;
      frame.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE) ;
  
      action1 = new JButton("Start");
      action2 = new JButton("Exit");
      lbl = new JLabel ("Welcome to the Matrix Encoder/Decoder!!!");
      setLayout(new FlowLayout());
  
      add (lbl) ;
      add(action1, BorderLayout.CENTER);
      action1.addActionListener (this);
      add(action2, BorderLayout.CENTER);
      action2.addActionListener (this);
  }
  @Override
  public void actionPerformed(ActionEvent event) {
      // TODO Auto-generated method stub
      OptionsMenu x = new OptionsMenu();
      if (event.getSource() == action1)
      {
          System.exit(0);
          x.OptionsMenu();
      }
      else if(event.getSource() == action2){
        System.exit(0);
      }
  
  }
  </code></pre>
  
  <p>}
  When the Start Button is clicked, the new menu comes up all fine and good, but the first menu stays open.  Is there a way to close this first menu AND open the second menu with the first button click?  I'm very new to GUI so the simplest solution would be very helpful.  On a side note is there a simple way to move the Start button to the next line?  Thanks</p>