private List<Integer> buildSourceList(int length) {
        List<Integer> l = new ArrayList<>();
        for (int i = 0; i < length; ++i) {
            l.add(i);
        }
        return l;
    }
@author huangfei1101 (fei.hf at alibaba-inc dot com)
@date 2021/12/30
ttl2-compatible/src/test/java/com/alibaba/demo/ttl/TtlWrapperTypeInferenceProblemShowcase.java