Here you can find the source of getDefaultDateFormatWithoutTimeZone( TimeZone zone)
private static synchronized SimpleDateFormat getDefaultDateFormatWithoutTimeZone( TimeZone zone)
//package com.java2s; /*//from ww w. j a v a2s . c o m * Copyright (C) 2010 Chair of Artificial Intelligence and Applied Informatics * Computer Science VI, University of Wuerzburg * * This is free software; you can redistribute it and/or modify it under the * terms of the GNU Lesser General Public License as published by the Free * Software Foundation; either version 3 of the License, or (at your option) any * later version. * * This software 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 Lesser General Public License for more * details. * * You should have received a copy of the GNU Lesser General Public License * along with this software; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA, or see the FSF * site: http://www.fsf.org. */ import java.text.SimpleDateFormat; import java.util.HashMap; import java.util.Map; import java.util.TimeZone; public class Main { private static final Map<TimeZone, SimpleDateFormat> DATE_FORMAT_WITHOUT_TIME_ZONE_MAP = new HashMap<>(); private static synchronized SimpleDateFormat getDefaultDateFormatWithoutTimeZone( TimeZone zone) { SimpleDateFormat simpleDateFormat = DATE_FORMAT_WITHOUT_TIME_ZONE_MAP .get(zone); if (simpleDateFormat == null) { simpleDateFormat = DATE_FORMAT_WITHOUT_TIME_ZONE_MAP.get(null); SimpleDateFormat clone = (SimpleDateFormat) simpleDateFormat .clone(); clone.setTimeZone(zone); DATE_FORMAT_WITHOUT_TIME_ZONE_MAP.put(zone, clone); } return simpleDateFormat; } }