Wie verwende ich JFileChooser, um ein Bild in einem JFrame oder JPanel anzuzeigen?

Ich habe ein Programm erstellt, mit dem das Format eines Bilds geändert werden kann. Alles funktioniert, aber wenn ich ein Bild über JFileChooser öffne, erhalte ichjava.lang.ClassCastException. Bitte kann mir jemand helfen. Ich glaube, ich mache einen Fehler bei der Verwendung der Dateiauswahl. Ich bin Anfänger, kann mir jemand so schnell wie möglich helfen?

 package helloWorld;

   import java.io.*;
   import java.util.TreeSet;
   import java.awt.*;
   import java.awt.event.*;
   import java.awt.geom.AffineTransform;
   import java.awt.image.*;
   import javax.imageio.*;
   import javax.swing.*;
   import javax.swing.filechooser.FileNameExtensionFilter;

   public class SaveImage extends Component implements Action Listener {

    String descs[] = {
    "Original", 
        "Convolve : LowPass",
        "Convolve : Sharpen", 
        "LookupOp",
    };

    int opIndex;
    private BufferedImage bi, biFiltered;
    private BufferedImage temp;
    int w, h;

    public static final float[] SHARPEN3x3 = { // sharpening filter kernel
        0.f, -1.f,  0.f,
       -1.f,  5.f, -1.f,
        0.f, -1.f,  0.f
    };

    public static final float[] BLUR3x3 = {
        0.1f, 0.1f, 0.1f,    // low-pass filter kernel
        0.1f, 0.2f, 0.1f,
        0.1f, 0.1f, 0.1f
    };

    public SaveImage()

    {

        try {
            bi = ImageIO.read(new File("")); // yahan kisi image ka path daal de
            w = bi.getWidth(null);
            h = bi.getHeight(null);
            if (bi.getType() != BufferedImage.TYPE_INT_RGB) {
                BufferedImage bi2 =
                    new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
                Graphics big = bi2.getGraphics();
                big.drawImage(bi, 0, 0, null);
                biFiltered = bi = bi2;
            }
        } catch (IOException e) {
            System.out.println("Image could not be read");
            System.exit(1);
        }
    }


    public void setimg( String path){}


    public Dimension getPreferredSize() {
        return new Dimension(w, h);
    }

    String[] getDescriptions() {
        return descs;
    }

    void setOpIndex(int i) {
        opIndex = i;
    }

    public void paint(Graphics g) {
        filterImage();
        g.drawImage(biFiltered, 0, 0, null);
    }

    int lastOp;
    public void filterImage() {
        BufferedImageOp op = null;

        if (opIndex == lastOp) {
            return;
        }
        lastOp = opIndex;
        switch (opIndex) {

        case 0: biFiltered = bi; /* original */
                return; 
        case 1:  /* low pass filter */
        case 2:  /* sharpen */
            float[] data = (opIndex == 1) ? BLUR3x3 : SHARPEN3x3;
            op = new ConvolveOp(new Kernel(3, 3, data),
                                ConvolveOp.EDGE_NO_OP,
                                null);

            break;

        case 3 : /* lookup */
            byte lut[] = new byte[256];
            for (int j=0; j<256; j++) {
                lut[j] = (byte)(256-j); 
            }
            ByteLookupTable blut = new ByteLookupTable(0, lut); 
            op = new LookupOp(blut, null);
            break;
        }


        biFiltered = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
        op.filter(bi, biFiltered);
    }

    /* Return the formats sorted alphabetically and in lower case */
    public String[] getFormats() {
        String[] formats = ImageIO.getWriterFormatNames();
        TreeSet<String> formatSet = new TreeSet<String>();
        for (String s : formats) {
            formatSet.add(s.toLowerCase());
        }
        return formatSet.toArray(new String[0]);
    }


     public void actionPerformed(ActionEvent e) {

         if (e.getActionCommand()=="browse")
         {
             //yahan pe bhundd h browse ka
             JFileChooser file = new JFileChooser();
            file.setCurrentDirectory(new File(System.getProperty("user.home")));
            FileNameExtensionFilter filter = new             FileNameExtensionFilter("*.Images","jpg", "gif", "png" );
            file.addChoosableFileFilter(filter);
            int result = file.showSaveDialog(null);
            if (result==JFileChooser.APPROVE_OPTION)
            {
                File selectedFile = file.getSelectedFile();
                String Path = selectedFile.getAbsolutePath();
            try{
                setimg(Path);// bi = ImageIO.read(new File(Path));
            //  temp = new BufferedImage(Path);//       label.setIcon(ResizeImage(Path));
                //}
            //  catch(IOException e1){
                    System.out.println("file not found");
                //}
            }
            else if(result== JFileChooser.CANCEL_OPTION)
            {
            //  ImageIcon Mimage = new      ImageIcon("C:\\Users\\Hasnain\\Downloads\\1.jpg");
                System.out.println("No file choosed");
                //label.setIcon(Mimage);
            }    
         }

         JComboBox cb = (JComboBox)e.getSource();
         if (cb.getActionCommand().equals("SetFilter")) {
             setOpIndex(cb.getSelectedIndex());
             repaint();
         } else if (cb.getActionCommand().equals("Formats")) {
             /* Save the filtered image in the selected format.
              * The selected item will be the name of the format to use
              */
             String format = (String)cb.getSelectedItem();
             /* Use the format name to initialise the file suffix.
              * Format names typically correspond to suffixes
              */
             File saveFile = new File("savedimage."+format);
             JFileChooser chooser = new JFileChooser();
             chooser.setSelectedFile(saveFile);
             int rval = chooser.showSaveDialog(cb);
             if (rval == JFileChooser.APPROVE_OPTION) {
                 saveFile = chooser.getSelectedFile();
                 /* Write the filtered image in the selected format,
                  * to the file chosen by the user.
                  */
                 try {
                     ImageIO.write(biFiltered, format, saveFile);
                 } catch (IOException ex) {
                 }
             }
         }
    };

    public static void main(String s[]) {
        JButton button = new JButton("Browse");
        button.setBounds(300, 300, 100, 40);

        JFrame f = new JFrame("Save Image Sample");
        f.addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent e) {System.exit(0);}
        });
        SaveImage si = new SaveImage();
        f.add("Center", si);
        JComboBox choices = new JComboBox(si.getDescriptions());
        choices.setActionCommand("SetFilter");
        choices.addActionListener(si);
        JComboBox formats = new JComboBox(si.getFormats());
        formats.setActionCommand("Formats");
        formats.addActionListener(si);
        JPanel panel = new JPanel();
        panel.add(button);
        button.setEnabled(true);

        panel.add(choices);
        panel.add(new JLabel("Save As"));
        panel.add(formats);
        f.add("South", panel);
        f.pack();
        f.setVisible(true);
        button.addActionListener(si);
        button.setActionCommand("browse");
    }
}  

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