Here you can find the source of doubleToString(Double num)
public static String doubleToString(Double num)
//package com.java2s; //License from project: BSD License public class Main { public static String doubleToString(Double num) { java.text.NumberFormat f = java.text.NumberFormat.getInstance(); f.setGroupingUsed(false);//from w ww.j a v a 2s. com return f.format(num); } }