content: /*
   * Tencent is pleased to support the open source community by making Angel available.
   *
   * Copyright (C) 2017-2018 THL A29 Limited, a Tencent company. All rights reserved.
   *
   * Licensed 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
   *
   * https://opensource.org/licenses/Apache-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.
   *
   */
  package com.tencent.angel.sona.tree.stats.hash;
  
  public class Mix64Hash extends Int2IntHash {
      public Mix64Hash(int size) {
          super(size);
      }
  
      protected int doHash(int key) {
          int code = key;
          code = (~code) + (code << 21); // code = (code << 21) - code - 1;
          code = code ^ (code >> 24);
          code = (code + (code << 3)) + (code << 8); // code * 265
          code = code ^ (code >> 14);
          code = (code + (code << 2)) + (code << 4); // code * 21
          code = code ^ (code >> 28);
          code = code + (code << 31);
          return code;
      }
  
      @Override
      public Int2IntHash clone() {
          Mix64Hash copy = new Mix64Hash(size);
          copy.buffer = this.buffer;
          return copy;
      }
  
      @Override
      public boolean equalsIgnoreSize(Int2IntHash other) {
          return other instanceof Mix64Hash;
      }
  }
  