code: /*
   * Copyright (C) 2013 The Android Open Source Project
   *
   * 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
   *
   *      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.
   */
  
  package com.lody.virtual.helper.collection;
  
  class ContainerHelpers {
      static final int[] EMPTY_INTS = new int[0];
      static final long[] EMPTY_LONGS = new long[0];
      static final Object[] EMPTY_OBJECTS = new Object[0];
  
      public static int idealIntArraySize(int need) {
          return idealByteArraySize(need * 4) / 4;
      }
  
      public static int idealLongArraySize(int need) {
          return idealByteArraySize(need * 8) / 8;
      }
  
      public static int idealByteArraySize(int need) {
          for (int i = 4; i < 32; i++)
              if (need <= (1 << i) - 12)
                  return (1 << i) - 12;
  
          return need;
      }
  
      public static boolean equal(Object a, Object b) {
          return a == b || (a != null && a.equals(b));
      }
  
      // This is Arrays.binarySearch(), but doesn't do any argument validation.
      static int binarySearch(int[] array, int size, int value) {
          int lo = 0;
          int hi = size - 1;
  
          while (lo <= hi) {
              int mid = (lo + hi) >>> 1;
              int midVal = array[mid];
  
              if (midVal < value) {
                  lo = mid + 1;
              } else if (midVal > value) {
                  hi = mid - 1;
              } else {
                  return mid;  // value found
              }
          }
          return ~lo;  // value not present
      }
  
      static int binarySearch(long[] array, int size, long value) {
          int lo = 0;
          int hi = size - 1;
  
          while (lo <= hi) {
              final int mid = (lo + hi) >>> 1;
              final long midVal = array[mid];
  
              if (midVal < value) {
                  lo = mid + 1;
              } else if (midVal > value) {
                  hi = mid - 1;
              } else {
                  return mid;  // value found
              }
          }
          return ~lo;  // value not present
      }
  }
  