なぜか変換失敗する@Jenova

Example.java

@Jenova(
    @Lambda(name="fn", type=Function.class)
)
public class Example {
    public List<String> transform(List<Integer> l) {
        l = Lists.transform(l, new fn<Integer, Integer>() {{
            return _1;
        }});
        return Lists.transform(l, new fn<Integer, String>() {{
            return Integer.toString(_1 * 2);
        }});
    }
}