protected void checkLeaf(SimulatedArchivalUnit sau) {
   log.debug("checkLeaf()");
   String parent = sau.getUrlRoot() + "/branch1";
   CachedUrlSetSpec spec = new RangeCachedUrlSetSpec(parent);
   CachedUrlSet set = sau.makeCachedUrlSet(spec);
   Iterator setIt = set.contentHashIterator();
   ArrayList childL = new ArrayList(16);
   while (setIt.hasNext()) {
     childL.add(((CachedUrlSetNode) setIt.next()).getUrl());
   }
   String[] expectedA =
       new String[] {
         parent,
         parent + "/001file.html",
         parent + "/001file.txt",
         parent + "/002file.html",
         parent + "/002file.txt",
         parent + "/branch1",
         parent + "/branch1/001file.html",
         parent + "/branch1/001file.txt",
         parent + "/branch1/002file.html",
         parent + "/branch1/002file.txt",
         parent + "/branch1/index.html",
         parent + "/branch2",
         parent + "/branch2/001file.html",
         parent + "/branch2/001file.txt",
         parent + "/branch2/002file.html",
         parent + "/branch2/002file.txt",
         parent + "/branch2/index.html",
         parent + "/index.html",
       };
   assertIsomorphic(expectedA, childL);
 }
  private void checkHashSet(
      SimulatedArchivalUnit sau, boolean namesOnly, boolean filter, byte[] expected)
      throws Exception {
    enableFilter(sau, filter);
    CachedUrlSet set = sau.getAuCachedUrlSet();
    byte[] hash = getHash(set, namesOnly);
    assertEquals(expected, hash);

    String parent = sau.getUrlRoot() + "/branch1";
    CachedUrlSetSpec spec = new RangeCachedUrlSetSpec(parent);
    set = sau.makeCachedUrlSet(spec);
    byte[] hash2 = getHash(set, namesOnly);
    assertFalse(Arrays.equals(hash, hash2));
  }