Java “怎么做？”；substr"；GroupOperation中的操作Id为spring数据mongodb？

如何在spring data mongodb中实现此操作

$group: {
  "_id": {orderDate: {"$substr": ["$localDate",0,params.getDateType]},storeId: "$storeId"},
  "date": {"$last": {"$substr": ["$localDate",0,params.getDateType]}
},

到目前为止，我已经试过了

GroupOperation groupOperation = Aggregation.group(String.valueOf(new BasicDBObject("orderDate",
        StringOperators.Substr.valueOf("localDate").substring(0,dateType))))
    .last(String.valueOf(new BasicDBObject("orderDate",
        StringOperators.Substr.valueOf("localDate").substring(0,dateType)))).as("date")

提前谢谢