How to get number of days between two calendar instance?

Question

I want to find the difference between two Calendar objects in number of days if there is date change like If clock ticked from 23:59-0:00 there should be a day

Answer 1

Kotlin solution, purely relies on Calendar. At the end gives exact number of days difference. Inspired by @Jk1

 private fun daysBetween(startDate: Calendar, endDate: Calendar): Long {
        val start = Calendar.getInstance().apply {
            timeInMillis = 0
            set(Calendar.DAY_OF_YEAR, startDate.get(Calendar.DAY_OF_YEAR))
            set(Calendar.YEAR, startDate.get(Calendar.YEAR))
        }.timeInMillis
        val end = Calendar.getInstance().apply {
            timeInMillis = 0
            set(Calendar.DAY_OF_YEAR, endDate.get(Calendar.DAY_OF_YEAR))
            set(Calendar.YEAR, endDate.get(Calendar.YEAR))
        }.timeInMillis
        val differenceMillis = end - start
        return TimeUnit.MILLISECONDS.toDays(differenceMillis)
    }