@Override
  public int positionedRead(long position, byte[] buffer, int offset, int length)
      throws IOException {
    seek(position);
    return read(buffer, offset, length);
  }
@Test
  public void positionedRead() throws IOException, AlluxioException {
    AlluxioURI ufsPath = getUfsPath();
    createFile(ufsPath, CHUNK_SIZE);
    try (FileInStream inStream = getStream(ufsPath)) {
      byte[] res = new byte[CHUNK_SIZE / 2];
      assertEquals(CHUNK_SIZE / 2,
          inStream.positionedRead(CHUNK_SIZE / 2, res, 0, CHUNK_SIZE / 2));
      assertTrue(BufferUtils.equalIncreasingByteArray(CHUNK_SIZE / 2, CHUNK_SIZE / 2, res));
    }
  }