@Nullable
private Node getSelectedNode() {
TreePath leadSelectionPath = myTree.getLeadSelectionPath();
if (leadSelectionPath == null) return null;
DefaultMutableTreeNode node = (DefaultMutableTreeNode) leadSelectionPath.getLastPathComponent();
return node instanceof Node ? (Node) node : null;
}
public static void collapseAll(final JTree tree, final int keepSelectionLevel) {
final TreePath leadSelectionPath = tree.getLeadSelectionPath();
// Collapse all
int row = tree.getRowCount() - 1;
while (row >= 0) {
tree.collapseRow(row);
row--;
}
final DefaultMutableTreeNode root = (DefaultMutableTreeNode) tree.getModel().getRoot();
tree.expandPath(new TreePath(root));
if (leadSelectionPath != null) {
final Object[] path = leadSelectionPath.getPath();
final Object[] pathToSelect =
new Object
[path.length > keepSelectionLevel && keepSelectionLevel >= 0
? keepSelectionLevel
: path.length];
System.arraycopy(path, 0, pathToSelect, 0, pathToSelect.length);
if (pathToSelect.length == 0) return;
selectPath(tree, new TreePath(pathToSelect));
}
}