protected BaseTreeTableModel(TreeInfoContext ct, String[] ccol, String[] cn) {
   super(null, false);
   context = ct;
   setColIndex(ccol);
   setColCaption(cn);
   DataSetTreeNode dstn = TreeUtils.createRootNode(ct.getCaption());
   setRoot(dstn);
   CreateData();
 }
 public void setString(String key, String value) {
   context.setString(key, value);
 }
 public String getString(String key) {
   return context.getString(key, "");
 }