Here you can find the source of sleep(long sleepTime)
public static boolean sleep(long sleepTime)
//package com.java2s; //License from project: Open Source License public class Main { public static boolean sleep(long sleepTime) { try {//from w w w . ja v a2 s.c o m Thread.sleep(sleepTime); return true; } catch (InterruptedException e) { Thread.currentThread().interrupt(); return false; } } }