Here you can find the source of dateToLong(final Date date)
public static long dateToLong(final Date date)
//package com.java2s; /*/*from w ww. j a v a2 s . co m*/ * Copyright 2002-2016 The Jamocha Team * * * 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.jamocha.org/ * * 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.Calendar; import java.util.Date; public class Main { public static long dateToLong(final Date date) { final Calendar cal = Calendar.getInstance(); cal.setTime(date); return cal.getTimeInMillis(); } }