public void valueChanged(TreeSelectionEvent e) {
				TreePath path = e.getPath();
				Object[] ancs = path.getPath();
				Category[] categories = new Category[ancs.length];
				for (int i = 0; i < categories.length; i++) {
					categories[i] = (Category) ((DefaultMutableTreeNode) ancs[i]).getUserObject();
				}
				try {
					fillProductList(categories);
				} catch (Exception q) {
					System.err
							.println("Die Produktliste konnte nicht geladen werden (Categories.class)");
					q.printStackTrace(System.err);
				}
			}