Function<Integer, Integer> adder =
        new Function<Integer, Integer>() {
          @Override
          public Integer apply(Integer from) {
            return from + holder.value;
          }
        };

    // Since holder.value is 2, applying 4 should yield 6.
    assertEquals(6, adder.apply(4).intValue());

    Function<Integer, Integer> adder =
        new Function<Integer, Integer>() {
          @Override
          public Integer apply(Integer from) {
            return from + holder.value;
          }
        };

    // Since holder.value is 2, applying 4 should yield 6.
    assertEquals(6, adder.apply(4).intValue());