Java tutorial
/* Copyright 2007 batcage@gmail.com 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. */ //package com.gcalsync.util; /** * * @author Thomas Oldervoll, thomas@zenior.no * @author $Author$ * @version $Rev: 40 $ * @date $Date$ */ import java.util.Calendar; import java.util.Date; public class Util { /** * Determines if given times span at least an entire day * * @param startTime starting time in ms since 1970 Jan 1 * @param endTime ending time in ms since 1970 Jan 1 * @returns <code>true</code>: starts and ends daily at * midnight<br><code>false</code> otherwise */ public static boolean isAllDay(long startTime, long endTime) { boolean startsMidnight = isMidnight(startTime); boolean endsMidnight = isMidnight(endTime); long timeDiff = (endTime - startTime) / 1000 / 60 / 60; //daily if difference in hours is a multiple of 24 boolean daily = (timeDiff >= 24) && ((timeDiff % 24) == 0); //starts and ends daily at 12:00am return (daily && startsMidnight && endsMidnight); } public static boolean isMidnight(long time) { Calendar calendar = Calendar.getInstance(); calendar.setTime(new Date(time)); return isMidnight(calendar); } private static boolean isMidnight(Calendar calendar) { return (calendar.get(Calendar.HOUR_OF_DAY) == 0) && (calendar.get(Calendar.MINUTE) == 0); } }