Here you can find the source of hoursFrom(Date date, int amount, String format)
public static String hoursFrom(Date date, int amount, String format)
//package com.java2s; /******************************************************************************* * Copyright (c) 2010 Oobium, Inc./*from w w w .java2 s . c om*/ * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/epl-v10.html * * Contributors: * Jeremy Dowdall <jeremy@oobium.com> - initial API and implementation ******************************************************************************/ import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Date; public class Main { public static Date hoursFrom(Date date, int amount) { Calendar cal = Calendar.getInstance(); cal.setTime(date); cal.add(Calendar.HOUR_OF_DAY, amount); return cal.getTime(); } public static String hoursFrom(Date date, int amount, String format) { SimpleDateFormat sdf = new SimpleDateFormat(format); return sdf.format(hoursFrom(date, amount)); } private static Date add(Date date, int field, int amount) { Calendar cal = Calendar.getInstance(); cal.setTime(date); cal.add(field, amount); return cal.getTime(); } }