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import java.awt.BorderLayout;
import java.util.Enumeration;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.event.TreeSelectionEvent;
import javax.swing.event.TreeSelectionListener;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.TreeModel;
import javax.swing.tree.TreeNode;
import javax.swing.tree.TreePath;
public class MainClass {
public static void main(String args[]) {
JFrame frame = new JFrame("Traverse Tree");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JTree tree = new JTree();
tree.setRootVisible(true);
TreeModel model = tree.getModel();
Object rootObject = model.getRoot();
if ((rootObject != null) && (rootObject instanceof DefaultMutableTreeNode)) {
DefaultMutableTreeNode r = (DefaultMutableTreeNode) rootObject;
printDescendents(r);
Enumeration breadth = r.breadthFirstEnumeration();
Enumeration depth = r.depthFirstEnumeration();
Enumeration preOrder = r.preorderEnumeration();
printEnumeration(breadth, "Breadth");
printEnumeration(depth, "Depth");
printEnumeration(preOrder, "Pre");
}
TreeSelectionListener treeSelectionListener = new TreeSelectionListener() {
public void valueChanged(TreeSelectionEvent treeSelectionEvent) {
JTree treeSource = (JTree) treeSelectionEvent.getSource();
TreePath path = treeSource.getSelectionPath();
System.out.println(path);
System.out.println(path.getPath());
System.out.println(path.getParentPath());
System.out.println(((DefaultMutableTreeNode) path.getLastPathComponent()).getUserObject());
System.out.println(path.getPathCount());
}
};
tree.addTreeSelectionListener(treeSelectionListener);
JScrollPane scrollPane = new JScrollPane(tree);
frame.add(scrollPane, BorderLayout.CENTER);
frame.setSize(300, 400);
frame.setVisible(true);
}
private static void printEnumeration(Enumeration e, String label) {
System.out.println("-----" + label + "-----");
while (e.hasMoreElements()) {
System.out.println(e.nextElement());
}
}
public static void printDescendents(TreeNode root) {
System.out.println(root);
Enumeration children = root.children();
if (children != null) {
while (children.hasMoreElements()) {
printDescendents((TreeNode) children.nextElement());
}
}
}
}
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