}

  /** Compares the contents of the two {@link InputStream}s for equality. */
  static boolean contentsEqual(InputStream in1, InputStream in2) throws IOException {
    byte[] buf1 = createBuffer();
    byte[] buf2 = createBuffer();
    while (true) {
      int read1 = read(in1, buf1, 0, BUFFER_SIZE);
      int read2 = read(in2, buf2, 0, BUFFER_SIZE);
      if (read1 != read2 || !arraysEqual(buf1, buf2, read1)) {