Here you can find the source of getDateTimeString(Date date, int format, Locale currentLocale)
private static String getDateTimeString(Date date, int format, Locale currentLocale)
//package com.java2s; import java.text.DateFormat; import java.util.Date; import java.util.HashMap; import java.util.Locale; import java.util.Map; public class Main { private static final Map<String, DateFormat> dateFormats = new HashMap<String, DateFormat>(); private static String getDateTimeString(Date date, int format, Locale currentLocale) { String key = format + "_" + currentLocale.toString(); DateFormat formatter = dateFormats.get(key); if (formatter == null) { formatter = DateFormat.getDateTimeInstance(format, format, currentLocale);//from ww w .j a va2 s .c o m dateFormats.put(key, formatter); } return formatter.format(date); } }