package io.xujiaji.plugin.util; import javax.swing.*; import javax.swing.tree.TreeNode; import javax.swing.tree.TreePath; import java.util.Enumeration; public class UIUtil { public static void expandTree(JTree tree) { TreeNode root = (TreeNode) tree.getModel().getRoot(); expandAll(tree, new TreePath(root), true); } private 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); } } }