assertEquals(7, (int) newValue);
    assertEquals(7, (int) map.getInstance(TypeToken.of(Integer.class)));

    // Won't compile: map.putInstance(Double.class, new Long(42));
  }

  public void testNull() {
    assertThrows(
        NullPointerException.class,
        () -> map.putInstance((TypeToken<Integer>) null, Integer.valueOf(1)));
    map.putInstance(Integer.class, null);

        .build();
  }

  private static Iterable<Striped<?>> allImplementations() {
    return concat(strongImplementations(), weakImplementations());
  }

  public void testNull() throws Exception {
    for (Striped<?> striped : allImplementations()) {
      new NullPointerTester().testAllPublicInstanceMethods(striped);
    }
  }

  public void testSizes() {

        .build();
  }

  private static Iterable<Striped<?>> allImplementations() {
    return concat(strongImplementations(), weakImplementations());
  }

  public void testNull() throws Exception {
    for (Striped<?> striped : allImplementations()) {
      new NullPointerTester().testAllPublicInstanceMethods(striped);
    }
  }

  public void testSizes() {