我为一个配置单元项目编写了一个新的自定义项，但返回类型不是日期对象，而是一个奇怪的结构。正确的返回类型是什么？

@Description(name = "udf_good_date", value = "_FUNC_(datestring):DATE", extended = "")
@UDFType(deterministic = true, stateful = false)
public class GoodDateAsDateUDF extends UDF {

    public Date evaluate(String a) {
        return Utils.getGoodDate(a);
    }

}

试一试：

select default.udf_good_date('10/20/1983);

奇怪的是：

+----------------------------------------------------------------------------------------------------------------------+--+
|                                                         _c0                                                          |
+----------------------------------------------------------------------------------------------------------------------+--+
| {"fasttime":125733600000,"cdate":{"cachedyear":1983,"cachedfixeddatejan1":720259,"cachedfixeddatenextjan1":720624}}  |
+----------------------------------------------------------------------------------------------------------------------+--+