Java tutorial
//package com.java2s; /* * Copyright 2015-2017 the original author or authors * * This software is licensed under the Apache License, Version 2.0, * the GNU Lesser General Public License version 2 or later ("LGPL") * and the WTFPL. * You may choose either license to govern your use of this software only * upon the condition that you accept all of the terms of either * the Apache License 2.0, the LGPL 2.1+ or the WTFPL. */ import java.util.Iterator; import java.util.Random; import java.util.Set; public class Main { public static <T> T getRandomFrom(Set<T> set, Random random) { int randomIndex = random.nextInt(set.size()); Iterator<T> iterator = set.iterator(); for (int i = 0; i < randomIndex; i++) { if (!iterator.hasNext()) break; iterator.next(); } return iterator.next(); } }