assertEquals(mod, unmod);
    mod.put("foo", 1);
    assertTrue(unmod.containsEntry("foo", 1));
    assertEquals(mod, unmod);
  }

  @SuppressWarnings("unchecked")
  public void testUnmodifiableMultimapEntries() {
    Multimap<String, Integer> mod = HashMultimap.create();
    Multimap<String, Integer> unmod = Multimaps.unmodifiableMultimap(mod);
    mod.put("foo", 1);