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vness8558

Error message:
Uncaught error fetching image:
java.lang.NullPointerException
at sun.awt.image.URLImageSource.getConnection(URLImageSource.java:97)
at sun.awt.image.URLImageSource.getDecoder(URLImageSource.java:106)
at sun.awt.image.InputStreamImageSource.doFetch(InputStreamImageSource.java:240)
at sun.awt.image.ImageFetcher.fetchloop(ImageFetcher.java:172)
at sun.awt.image.ImageFetcher.run(ImageFetcher.java:136)
Source code:
    private void jbInit() throws Exception {
        setIconImage(Toolkit.getDefaultToolkit().createImage(Frame3.class.getResource("logo.gif")));
        contentPane = (JPanel) getContentPane();
        contentPane.setLayout(borderLayout1);
        this.setJMenuBar(jMenuBar1);
        setSize(new Dimension(400, 300));
        setTitle("Main Menu");
        jMenu1.setText("sdfsd");
        jMenuItem1.setText("ssdfsdf");
        jMenuItem2.setText("sdf");
        jMenuItem3.setText("sd");
        jMenuItem4.setText("sdfsdf");
        jMenuBar1.setOpaque(false);
        jMenuBar1.add(jMenu1);
        jMenu1.add(jMenuItem1);
        jMenu1.add(jMenuItem2);
        jMenu1.add(jMenuItem3);
        jMenu1.add(jMenuItem4);
    }

seakey

setIconImage(Toolkit.getDefaultToolkit().createImage(Frame3.class.getResource("logo.gif"))); This sentence is incorrect
ImageIcon=new ImageIcon(getClass().getResource("logo.gif"));