code: /*
   *  Copyright 2011 Alexey Andreev.
   *
   *  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;
  
  import java.util.Arrays;
  
  /**
   * @author Lody
   */
  public class IntArray {
      private static final int[] EMPTY_ARRAY = new int[0];
      private int[] mData;
      private int mSize;
  
      private IntArray() {
      }
  
      public IntArray(int capacity) {
          this.mData = new int[capacity];
      }
  
      public static IntArray of(int... values) {
          IntArray array = new IntArray();
          array.mData = Arrays.copyOf(values, values.length);
          array.mSize = values.length;
          return array;
      }
  
      public void clear() {
          mSize = 0;
      }
  
      public void optimize() {
          if (mSize > mData.length) {
              mData = Arrays.copyOf(mData, mSize);
          }
      }
  
      public int[] getAll() {
          return mSize > 0 ? Arrays.copyOf(mData, mSize) : EMPTY_ARRAY;
      }
  
      public int get(int index) {
          return mData[index];
      }
  
      public int[] getRange(int start, int end) {
          return Arrays.copyOfRange(mData, start, end);
      }
  
      public void set(int index, int value) {
          if (index >= mSize) {
              throw new IndexOutOfBoundsException("Index " + index + " is greater than the list size " + mSize);
          }
          mData[index] = value;
      }
  
      private void ensureCapacity() {
          if (mSize <= mData.length) {
              return;
          }
          int newCap = mData.length;
          while (mSize > newCap) {
              newCap = newCap * 3 / 2 + 1;
          }
          mData = Arrays.copyOf(mData, newCap);
      }
  
      public int size() {
          return mSize;
      }
  
      public void addAll(int[] items) {
          int target = mSize;
          mSize += items.length;
          ensureCapacity();
          System.arraycopy(items, 0, mData, target, items.length);
      }
  
      public void add(int item) {
          ++mSize;
          ensureCapacity();
          mData[mSize - 1] = item;
      }
  
      public void remove(int index) {
          remove(index, 1);
      }
  
      public void remove(int index, int count) {
          System.arraycopy(mData, index + count, mData, index, mSize - index - count);
          mSize -= count;
      }
  
      public boolean contains(int item) {
          for (int i = 0; i < mSize; ++i) {
              if (mData[i] == item) {
                  return true;
              }
          }
          return false;
      }
  }
  