Here you can find the source of randomInt()
public static double randomInt()
//package com.java2s; /*/*from w ww. j av a 2 s . co m*/ * Licensed to Elasticsearch under one or more contributor * license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright * ownership. Elasticsearch 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.concurrent.ThreadLocalRandom; public class Main { public static double randomInt() { return ThreadLocalRandom.current().nextInt(); } public static double randomInt(Integer i) { return ThreadLocalRandom.current().nextInt(i); } }