1090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson/* 21d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Copyright (C) 2008 The Guava Authors 3090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson * 4090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson * Licensed under the Apache License, Version 2.0 (the "License"); 5090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson * you may not use this file except in compliance with the License. 6090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson * You may obtain a copy of the License at 7090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson * 8090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson * http://www.apache.org/licenses/LICENSE-2.0 9090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson * 10090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson * Unless required by applicable law or agreed to in writing, software 11090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson * distributed under the License is distributed on an "AS IS" BASIS, 12090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson * See the License for the specific language governing permissions and 14090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson * limitations under the License. 15090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson */ 16090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson 17090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilsonpackage com.google.common.collect; 18090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson 19090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilsonimport com.google.common.annotations.GwtCompatible; 20090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson 21090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson/** 22090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson * Static methods for implementing hash-based collections. 23090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson * 24090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson * @author Kevin Bourrillion 25090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson * @author Jesse Wilson 26090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson */ 27090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson@GwtCompatible 28090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilsonfinal class Hashing { 29090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson private Hashing() {} 30090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson 31090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson /* 32090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson * This method was written by Doug Lea with assistance from members of JCP 33090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson * JSR-166 Expert Group and released to the public domain, as explained at 34090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson * http://creativecommons.org/licenses/publicdomain 351d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * 361d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * As of 2010/06/11, this method is identical to the (package private) hash 371d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * method in OpenJDK 7's java.util.HashMap class. 38090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson */ 39090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson static int smear(int hashCode) { 40090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson hashCode ^= (hashCode >>> 20) ^ (hashCode >>> 12); 41090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson return hashCode ^ (hashCode >>> 7) ^ (hashCode >>> 4); 42090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson } 43090f9b4c879985bc747c214f82c62471e60c7742Jesse Wilson} 44