Android Kotlin Calendar get 1st day of year and last day of year

first_and_last_day_of_year.kt

        // first day of year
        val cal = Calendar.getInstance()
        cal.set(Calendar.MONTH, 0)
        cal.set(Calendar.DAY_OF_MONTH, 1)
        val year_start = cal.get(Calendar.YEAR)
        val month_start = cal.get(Calendar.MONTH) // Mois de 0 à 11
        val day_start = cal.get(Calendar.DAY_OF_MONTH)
        textViewStartDate.setText("${String.format("%02d", day_start)}/${String.format("%02d", month_start+1)}/${String.format("%04d", year_start)}")

        // last day of year
        cal.set(Calendar.MONTH, 11)
        cal.set(Calendar.DAY_OF_MONTH, cal.getActualMaximum(Calendar.DAY_OF_MONTH))
        val year_end = cal.get(Calendar.YEAR)
        val month_end = cal.get(Calendar.MONTH) // Mois de 0 à 11
        val day_end = cal.get(Calendar.DAY_OF_MONTH)
        textViewEndDate.setText("${String.format("%02d", day_end)}/${String.format("%02d", month_end+1)}/${String.format("%04d", year_end)}")