Here you can find the source of isDST()
public static boolean isDST()
//package com.java2s; /*//from ww w.j av a2 s . com This file is part of the OdinMS Maple Story Server Copyright (C) 2008 Patrick Huy <patrick.huy@frz.cc> Matthias Butz <matze@odinms.de> Jan Christian Meyer <vimes@odinms.de> This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License version 3 as published by the Free Software Foundation. You may not use, modify or distribute this program under any other version of the GNU Affero General Public License. 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/>. */ import java.util.SimpleTimeZone; public class Main { public static boolean isDST() { return SimpleTimeZone.getDefault().useDaylightTime(); } }