Here you can find the source of hours(int hours)
public static Date hours(int hours)
//package com.java2s; /*//from w ww .j ava 2 s .co m * Licensed to J?rg Prante and xbib under one or more contributor * license agreements. See the NOTICE.txt file distributed with this work * for additional information regarding copyright ownership. * * Copyright (C) 2012 J?rg Prante and xbib * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as published * by the Free Software Foundation; either version 3 of the License, or * (at your option) any later version. * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Affero General Public License for more details. * * You should have received a copy of the GNU Affero General Public License * along with this program; if not, see http://www.gnu.org/licenses * or write to the Free Software Foundation, Inc., 51 Franklin Street, * Fifth Floor, Boston, MA 02110-1301 USA. * * The interactive user interfaces in modified source and object code * versions of this program must display Appropriate Legal Notices, * as required under Section 5 of the GNU Affero General Public License. * * In accordance with Section 7(b) of the GNU Affero General Public * License, these Appropriate Legal Notices must retain the display of the * "Powered by xbib" logo. If the display of the logo is not reasonably * feasible for technical reasons, the Appropriate Legal Notices must display * the words "Powered by xbib". */ import java.util.Calendar; import java.util.Date; public class Main { private static final Calendar cal = Calendar.getInstance(); public static Date hours(int hours) { return hours(new Date(), hours); } public static Date hours(Date date, int hours) { synchronized (cal) { cal.setTime(date); cal.add(Calendar.HOUR_OF_DAY, hours); return cal.getTime(); } } }