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import java.awt.Dimension;
import java.awt.Image;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.io.File;
import javax.swing.ImageIcon;
import javax.swing.JFileChooser;
import javax.swing.JLabel;
class LabelAccessory extends JLabel implements PropertyChangeListener {
private static final int PREFERRED_WIDTH = 125;
private static final int PREFERRED_HEIGHT = 100;
public LabelAccessory(JFileChooser chooser) {
setVerticalAlignment(JLabel.CENTER);
setHorizontalAlignment(JLabel.CENTER);
chooser.addPropertyChangeListener(this);
setPreferredSize(new Dimension(PREFERRED_WIDTH, PREFERRED_HEIGHT));
}
public void propertyChange(PropertyChangeEvent changeEvent) {
String changeName = changeEvent.getPropertyName();
if (changeName.equals(JFileChooser.SELECTED_FILE_CHANGED_PROPERTY)) {
File file = (File)changeEvent.getNewValue();
if (file != null) {
ImageIcon icon = new ImageIcon(file.getPath());
if (icon.getIconWidth() > PREFERRED_WIDTH) {
icon = new ImageIcon(icon.getImage().getScaledInstance(
PREFERRED_WIDTH, -1, Image.SCALE_DEFAULT));
if (icon.getIconHeight() > PREFERRED_HEIGHT) {
icon = new ImageIcon(icon.getImage().getScaledInstance(
-1, PREFERRED_HEIGHT, Image.SCALE_DEFAULT));
}
}
setIcon(icon);
}
}
}
}
public class JFileChooserAddingAccessoryPanels {
public static void main(String[] a){
JFileChooser fileChooser = new JFileChooser();
fileChooser.setAccessory(new LabelAccessory(fileChooser));
fileChooser.showOpenDialog(null);
}
}
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