Here you can find the source of generateUUID()
public static String generateUUID()
//package com.java2s; /*/*w w w . j a v a2 s .com*/ * Copyright 2009 Red Hat, Inc. * * Red Hat licenses this file to you under the Apache License, version 2.0 * (the "License"); you may not use this file except in compliance with the * License. You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations * under the License. */ import java.util.UUID; public class Main { /** * Returns a string of 16 HEX chars. * * @return */ public static String generateUUID() { UUID uuid = UUID.randomUUID(); return Long.toHexString(uuid.getMostSignificantBits()); } }