Here you can find the source of dayOfDate(Date s)
static public int dayOfDate(Date s) throws ParseException
//package com.java2s; //License from project: Open Source License import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Date; public class Main { /**/*from w w w . j a va 2s . c o m*/ * format pattern : yyyy-MM-dd */ public static final SimpleDateFormat FORMAT_YYYY_MM_DD = new SimpleDateFormat("yyyy-MM-dd"); static public int dayOfDate(Date s) throws ParseException { String d = FORMAT_YYYY_MM_DD.format(s); return Integer.parseInt(d.substring(8, 10)); } static public String format(Date date, String formatText) throws Exception { SimpleDateFormat format = new SimpleDateFormat(formatText); return format.format(date); } }