Howto close only one JFrame, and not the whole Application?

Question

I hava a Application (Just a JFrame).
I open a new JFrame doing some Wizard stuff.
The user should close the Wizard with the Window-Closer [x].
But: all open Frames dispose. How can i prevent that?
The Application uses:
         setDefaultCloseOperation(javax.swing.WindowConstants.DO_NOTHING_ON_CLOSE);
addWindowListener(new java.awt.event.WindowAdapter() {
    public void windowClosing(java.awt.event.WindowEvent evt) {
        System.gc();
        System.exit(0);
        //or alternative: dispose();
});The second JFrame uses:
frame.addWindowListener(new java.awt.event.WindowAdapter() {
    public void windowClosing(java.awt.event.WindowEvent evt) {
        frame.dispose();
});

Answer 1

System.exit(0) will close all windows in an application if you use it, as it will kill the whole program you have launched from the command-line, you need to call frame.dispose()