Here you can find the source of format(Date date, String format)
public static String format(Date date, String format)
//package com.java2s; //License from project: Open Source License import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Date; public class Main { public static String format(Date date) { return format(date, "yyyy-MM-dd HH:mm:ss"); }// ww w. j a va 2 s . c o m public static String format(Date date, String format) { SimpleDateFormat df = new SimpleDateFormat(format); return df.format(date); } public static Date format(String date) { Date dt = format(date, "yyyy-MM-dd HH:mm:ss"); if (dt == null) { return formatDate(date); } else { return dt; } } public static Date format(String date, String format) { SimpleDateFormat df = new SimpleDateFormat(format); try { return df.parse(date); } catch (ParseException e) { return null; } } public static String formatDate(Date date) { return format(date, "yyyy-MM-dd"); } public static Date formatDate(String date) { return format(date, "yyyy-MM-dd"); } }