Interner<Object> interner =
        Interners.newBuilder().weak().concurrencyLevel(concurrencyLevel).build();
    InternerImpl<Object> internerImpl = (InternerImpl<Object>) interner;
    assertEquals(Strength.WEAK, internerImpl.map.keyStrength());
    assertEquals(concurrencyLevel, internerImpl.map.concurrencyLevel);
  }


  public void testWeak_afterGC() throws InterruptedException {
    Integer canonical = new Integer(5);

    Interner<Object> interner =
        Interners.newBuilder().weak().concurrencyLevel(concurrencyLevel).build();
    InternerImpl<Object> internerImpl = (InternerImpl<Object>) interner;
    assertEquals(Strength.WEAK, internerImpl.map.keyStrength());
    assertEquals(concurrencyLevel, internerImpl.map.concurrencyLevel);
  }


  public void testWeak_afterGC() throws InterruptedException {
    Integer canonical = new Integer(5);

      }
    };

    abstract <R extends Comparable<R>, C extends Comparable<C>, V> Table<R, C, V> create(
        Table<R, C, V> contents);
  }

  public enum InternerImpl implements InternerImplEnum {
    WeakInternerImpl {
      @Override
      public <E> Interner<E> create(Collection<E> contents) {
        Interner<E> interner = Interners.newWeakInterner();

      }
    };

    abstract <R extends Comparable<R>, C extends Comparable<C>, V> Table<R, C, V> create(
        Table<R, C, V> contents);
  }

  public enum InternerImpl implements InternerImplEnum {
    WeakInternerImpl {
      @Override
      public <E> Interner<E> create(Collection<E> contents) {
        Interner<E> interner = Interners.newWeakInterner();