Here you can find the source of getBoolean()
public static boolean getBoolean()
//package com.java2s; /*//from w w w .j a v a2 s . co m * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF 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.Random; public class Main { private static Random rd = new Random(); public static boolean getBoolean() { return getIntegerMoreThanZeroLessThan(3) == 1; } public static int getIntegerMoreThanZeroLessThan(int n) { int res = rd.nextInt(n); while (res == 0) { res = rd.nextInt(n); } return res; } }