如何使用考虑两个字符串日期范围的标准在 Mongo DB 中构建 Spring Query

Question

I have to build a criteria of a find query using a date field which is stored in String format. The criteria I've written is like this:

Query findQuery = new Query()
findQuery.addCriteria(Criteria.where(mongoField).gt(startDate).lt(endDate));

where the "mongofield" is a String type, but "startDate" and "endDate" are a LocalDate type.

This criteria obviously doesn't work because the comparison is ineffective. I've found that I should use $expr operator together with $dateFromString, but I didn't find any clear example of use in Java code.

Please, can anyone help me in writing a good statement in Spring Java code?

Answer 1

You can convert LocalDate to a string and then compare

        LocalDate startDate = LocalDate.now();
        LocalDate endDate = LocalDate.now().plusDays(20);
        // Define time format converter
        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyyMMdd");
        // Convert LocalDate type to String type
        Criteria criteria = Criteria.where("mongoField").is("").gte(startDate.format(formatter)).lt(endDate.format(formatter));
        Query query = new Query(criteria);