@Override
  public boolean delete(PageId pageId) {
    return mFilter.delete(pageId);
  }
@Test
  public void delete() throws Exception {
    assertTrue(mCacheManager.put(PAGE_ID1, PAGE1_BYTES, SCOPE1));
    assertEquals(PAGE1_BYTES, mCacheManager.get(PAGE_ID1, PAGE1_BYTES, SCOPE1));
    assertTrue(mCacheManager.delete(PAGE_ID1));
    assertEquals(0, mCacheManager.get(PAGE_ID1, PAGE1_BYTES, SCOPE1));
    mCacheManager.updateWorkingSetSize();
    // cuckoo filter supports deleting, so PAGE_ID1 is really deleted
    assertEquals(0, mCacheManager.getShadowCachePages());
    assertEquals(mCacheManager.getShadowCacheBytes(), PAGE1_BYTES);
  }