Java tutorial
//package com.micrometa.km.ui.util; import java.util.Enumeration; import javax.swing.JTree; import javax.swing.tree.TreeNode; import javax.swing.tree.TreePath; public class TreeUtil { public static void expandAll(JTree tree, boolean expand) { TreeNode root = (TreeNode) tree.getModel().getRoot(); // Traverse tree from root expandAll(tree, new TreePath(root), expand); } public static void expandAll(JTree tree, TreePath parent, boolean expand) { // Traverse children TreeNode node = (TreeNode) parent.getLastPathComponent(); if (node.getChildCount() >= 0) { for (Enumeration e = node.children(); e.hasMoreElements();) { TreeNode n = (TreeNode) e.nextElement(); TreePath path = parent.pathByAddingChild(n); expandAll(tree, path, expand); } } // Expansion or collapse must be done bottom-up if (expand) { tree.expandPath(parent); } else { tree.collapsePath(parent); } } }