Here you can find the source of getGuid(Object clazz)
public static String getGuid(Object clazz)
//package com.java2s; //License from project: Open Source License import java.util.concurrent.atomic.AtomicInteger; public class Main { final static AtomicInteger seeds = new AtomicInteger(); public static String getGuid(Object clazz) { return getGuid(); }/* w w w.ja v a2 s . c o m*/ public static String getGuid() { long stamp = System.currentTimeMillis(); long id = seeds.incrementAndGet(); int current = seeds.get(); if (current > 1000) { seeds.compareAndSet(current, 0); } return (stamp + "-" + id); } }