Here you can find the source of nextDay(Date date, int day)
public static Date nextDay(Date date, int day)
//package com.java2s; //License from project: Apache License import java.util.*; public class Main { public static Date nextDay(Date date, int day) { Calendar cal = Calendar.getInstance(); if (date != null) { cal.setTime(date);//from w w w . j a v a2 s . c o m } cal.add(Calendar.DAY_OF_YEAR, day); return cal.getTime(); } }