Here you can find the source of nextHighestPowerOfTwo(long v)
public static long nextHighestPowerOfTwo(long v)
//package com.java2s; /**/* w ww . ja va 2 s.c om*/ * 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. */ public class Main { /** returns the next highest power of two, or the current value if it's already a power of two or zero*/ public static int nextHighestPowerOfTwo(int v) { v--; v |= v >> 1; v |= v >> 2; v |= v >> 4; v |= v >> 8; v |= v >> 16; v++; return v; } /** returns the next highest power of two, or the current value if it's already a power of two or zero*/ public static long nextHighestPowerOfTwo(long v) { v--; v |= v >> 1; v |= v >> 2; v |= v >> 4; v |= v >> 8; v |= v >> 16; v |= v >> 32; v++; return v; } }