Here you can find the source of atol(String s)
public static long atol(String s)
//package com.java2s; //License from project: Open Source License public class Main { public static long atol(String s) { if (s == null) return 0; long result = 0; try {//from w w w .j a v a2 s .c o m result = Long.parseLong(s); } catch (NumberFormatException e) { } return result; } }