Here you can find the source of randomString()
public static String randomString()
//package com.java2s; /*/*from w w w .j a v a 2 s . c om*/ * JBoss, Home of Professional Open Source * Copyright 2010, Red Hat Inc., and individual contributors as indicated * by the @authors tag. See the copyright.txt in the distribution for a * full listing of individual contributors. * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */ import java.util.UUID; import java.util.concurrent.ThreadLocalRandom; public class Main { public static String randomString() { return UUID.randomUUID().toString(); } public static String randomString(String prefix) { return prefix + "-" + ThreadLocalRandom.current().nextInt(0, Integer.MAX_VALUE); } }