取前一天12点之前两小时

 
        // 获取当前系统时间:2021-08-12T16:00
        LocalDate localDate = LocalDate.now(); 
        LocalDateTime dateTime = LocalDateTime.of(localDate, LocalTime.MIN).minusHours(2);
       //前一天12点前两小时：2021-08-11T22:00
        System.out.println(dateTime);