I want to make it like when I click a button, it will create a new file. Then the jTree will highlight the new file. Below are my code. Currently I create new file, i will show the new file but no highlight the file.
class FileTreeModel implements TreeModel {
private FileNode root;
public FileTreeModel(String directory) {
    root = new FileNode(directory);
}
public Object getRoot() {
    return root;
}
public Object getChild(Object parent, int index) {
    FileNode parentNode = (FileNode) parent;
    return new FileNode(parentNode, parentNode.listFiles()[index].getName());
}
public int getChildCount(Object parent) {
    FileNode parentNode = (FileNode) parent;
    if (parent == null || !parentNode.isDirectory()
            || parentNode.listFiles() == null) {
        return 0;
    }
    return parentNode.listFiles().length;
}
public boolean isLeaf(Object node) {
    return (getChildCount(node) == 0);
}
public int getIndexOfChild(Object parent, Object child) {
    FileNode parentNode = (FileNode) parent;
    FileNode childNode = (FileNode) child;
    return Arrays.asList(parentNode.list()).indexOf(childNode.getName());
}
public void valueForPathChanged(TreePath path, Object newValue) {
}
public void addTreeModelListener(TreeModelListener l) {
}
public void removeTreeModelListener(TreeModelListener l) {
}
}
class FileNode extends java.io.File {
public FileNode(String directory) {
    super(directory);
}
public FileNode(FileNode parent, String child) {
    super(parent, child);
}
@Override
public String toString() {
    return getName();
}
}
       jTree = new JTree();
        jTree.setBounds(new Rectangle(164, 66, 180, 421));
        jTree.setBackground(SystemColor.inactiveCaptionBorder);
        jTree.setBorder(BorderFactory.createTitledBorder(null, "",
                TitledBorder.LEADING, TitledBorder.TOP, new Font("Arial",
                        Font.BOLD, 12), new Color(0, 0, 0)));
        FileTreeModel model = new FileTreeModel(root);
        jTree.setRootVisible(false);
        jTree.setModel(model);
        expandAll(jTree);
public void expandAll(JTree tree) {
    int row = 0;
    while (row < tree.getRowCount()) {
        tree.expandRow(row);
        row++;
    }
   }