Here you can find the source of getTimeZoneDefault()
public static TimeZone getTimeZoneDefault()
//package com.java2s; /*//from w w w.j a v a2 s . c o m * Copyright 2017-2018 Crown Copyright * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ import java.util.TimeZone; public class Main { public static final String TIME_ZONE = "koryphe.timezone.default"; public static TimeZone getTimeZoneDefault() { return null != System.getProperty(TIME_ZONE) ? TimeZone.getTimeZone(System.getProperty(TIME_ZONE)) : null; } }