code: private Object eval(Bindings bindings, String expression) {
      try {
        return jsScriptEngine.eval(bindings, expression);
      } catch (javax.script.ScriptException t) {
        return new ScriptException(t.getCause().getMessage(), t.getCause());
      } catch (Exception t) {
        return new ScriptException(t);
      }
    }
docs: Evaluates an expression with the given bindings.
  
  @param bindings Bindings to use as engine scope
  @param expression JavaScript expression to evaluate
  @return evaluated expression result, return type depends on the expression.