Here you can find the source of getDateOffset(String date, int offset)
public static String getDateOffset(String date, int offset)
//package com.java2s; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Date; import java.util.GregorianCalendar; public class Main { public static String getDateOffset(String date, int offset) { // Date tempDate = getDateObj(date, "[/]"); Date tempDate = null;/*from ww w . j a va2 s . co m*/ if (date.indexOf("/") > 0) tempDate = getDateObj(date, "[/]"); if (date.indexOf("-") > 0) tempDate = getDateObj(date, "[-]"); tempDate = getDateAdd(tempDate, offset); return getFormatDateTime(tempDate, "yyyy/MM/dd"); } public static Date getDateObj(int year, int month, int day) { Calendar c = new GregorianCalendar(); c.set(year, month - 1, day); return c.getTime(); } public static Date getDateObj(String argsDate, String split) { String[] temp = argsDate.split(split); int year = Integer.valueOf(temp[0]); int month = Integer.valueOf(temp[1]); int day = Integer.valueOf(temp[2]); return getDateObj(year, month, day); } public static Date getDateObj() { Calendar c = new GregorianCalendar(); return c.getTime(); } public static Date getDateAdd(Date date, int amount) { Calendar cal = new GregorianCalendar(); cal.setTime(date); cal.add(GregorianCalendar.DATE, amount); return cal.getTime(); } public static String getFormatDateTime(Date date, String format) { SimpleDateFormat sdf = new SimpleDateFormat(format); return sdf.format(date); } }