top.offer(1);
    for (int i = 1; i < n; i++) {
      top.offer(0);
    }
    assertThat(top.topK()).containsExactlyElementsIn(Collections.nCopies(k, 0));
    assertThat(compareCalls[0]).isAtMost(10L * n * IntMath.log2(k, RoundingMode.CEILING));
  }

  public void testExceedMaxIteration() {
    /*
     * Bug #5692 occurred when TopKSelector called Arrays.sort incorrectly.
     */