content: /*
   * Copyright 2002-2019 Drew Noakes and contributors
   *
   *    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://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.
   *
   * More information about this project is available at:
   *
   *    https://drewnoakes.com/code/exif/
   *    https://github.com/drewnoakes/metadata-extractor
   */
  
  package com.drew.lang;
  
  import com.drew.lang.annotations.NotNull;
  
  import java.io.EOFException;
  import java.io.IOException;
  
  /**
   *
   * @author Drew Noakes https://drewnoakes.com
   */
  public class SequentialByteArrayReader extends SequentialReader
  {
      @NotNull
      private final byte[] _bytes;
      private int _index;
  
      @Override
      public long getPosition()
      {
          return _index;
      }
  
      public SequentialByteArrayReader(@NotNull byte[] bytes)
      {
          this(bytes, 0);
      }
  
      @SuppressWarnings("ConstantConditions")
      public SequentialByteArrayReader(@NotNull byte[] bytes, int baseIndex)
      {
          if (bytes == null)
              throw new NullPointerException();
  
          _bytes = bytes;
          _index = baseIndex;
      }
  
      @Override
      public byte getByte() throws IOException
      {
          if (_index >= _bytes.length) {
              throw new EOFException("End of data reached.");
          }
          return _bytes[_index++];
      }
  
      @NotNull
      @Override
      public byte[] getBytes(int count) throws IOException
      {
          if ((long)_index + count > _bytes.length) {
              throw new EOFException("End of data reached.");
          }
  
          byte[] bytes = new byte[count];
          System.arraycopy(_bytes, _index, bytes, 0, count);
          _index += count;
  
          return bytes;
      }
  
      @Override
      public void getBytes(@NotNull byte[] buffer, int offset, int count) throws IOException
      {
          if ((long)_index + count > _bytes.length) {
              throw new EOFException("End of data reached.");
          }
  
          System.arraycopy(_bytes, _index, buffer, offset, count);
          _index += count;
      }
  
      @Override
      public void skip(long n) throws IOException
      {
          if (n < 0) {
              throw new IllegalArgumentException("n must be zero or greater.");
          }
  
          if (_index + n > _bytes.length) {
              throw new EOFException("End of data reached.");
          }
  
          _index += n;
      }
  
      @Override
      public boolean trySkip(long n) throws IOException
      {
          if (n < 0) {
              throw new IllegalArgumentException("n must be zero or greater.");
          }
  
          if (_index + n > _bytes.length)  {
              _index = _bytes.length;
              return false;
          }
  
          _index += n;
  
          return true;
      }
  
      @Override
      public int available() {
          return _bytes.length - _index;
      }
  }
  