}

  // Intentionally using IdentityHashMap to test creation.
  @SuppressWarnings("IdentityHashMapBoxing")
  public void testIdentityHashMap() {
    IdentityHashMap<Integer, Integer> map = Maps.newIdentityHashMap();
    assertEquals(emptyMap(), map);
  }

  public void testConcurrentMap() {
    ConcurrentMap<Integer, Integer> map = Maps.newConcurrentMap();
    assertEquals(emptyMap(), map);
  }

  }

  // Intentionally using IdentityHashMap to test creation.
  @SuppressWarnings("IdentityHashMapBoxing")
  public void testIdentityHashMap() {
    IdentityHashMap<Integer, Integer> map = Maps.newIdentityHashMap();
    assertEquals(emptyMap(), map);
  }

  public void testConcurrentMap() {
    ConcurrentMap<Integer, Integer> map = Maps.newConcurrentMap();
    assertEquals(emptyMap(), map);
  }