import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.UIManager;
public class Main {
public static void main(String[] argv) throws Exception {
Icon leafIcon = new ImageIcon("leaf.gif");
Icon openIcon = new ImageIcon("open.gif");
Icon closedIcon = new ImageIcon("closed.gif");
UIManager.put("Tree.leafIcon", leafIcon);
UIManager.put("Tree.openIcon", openIcon);
UIManager.put("Tree.closedIcon", closedIcon);
JTree tree = new JTree();
JFrame f = new JFrame();
f.add(new JScrollPane(tree));
f.setSize(300, 300);
f.setVisible(true);
}
}