Java examples for java.util:Calendar Calculation
decrement One Day
/*//from w ww . ja v a 2s . c om * Copyright 2009 Yodlee, Inc. All Rights Reserved. Your use of this code * requires a license from Yodlee. Any such license to this code is * restricted to evaluation/illustrative purposes only. It is not intended * for use in a production environment, and Yodlee disclaims all warranties * and/or support obligations concerning this code, regardless of the terms * of any other agreements between Yodlee and you." */ //package com.java2s; import java.util.Calendar; public class Main { public static void main(String[] argv) throws Exception { Calendar calendar = Calendar.getInstance(); decrementOneDay(calendar); } public static void decrementOneDay(Calendar calendar) { int monthBeforeDecrement = calendar.get(Calendar.MONTH); calendar.add(Calendar.DAY_OF_YEAR, -1); int monthAfterDecrement = calendar.get(Calendar.MONTH); // if year changes setMinimalDaysInFirstWeek for New Year if (monthBeforeDecrement == Calendar.JANUARY && monthAfterDecrement == Calendar.DECEMBER) { calendar.setMinimalDaysInFirstWeek(calculateMinimalDaysInFirstWeek(calendar)); } } public static int calculateMinimalDaysInFirstWeek(Calendar calendar) { Calendar temp = (Calendar) calendar.clone(); temp.set(Calendar.DAY_OF_YEAR, 1); int firstDayOfJan = temp.get(Calendar.DAY_OF_WEEK); return 8 - firstDayOfJan; } }