List<PvUvBo> filterPvUvMap = pvUvMap.values().stream().collect(Collectors.toList());
Map<String, PvUvBo> pvUvMap = pvUvBoList.stream().
collect(Collectors.toMap(PvUvBo::getSourceCode, Function.identity()));
原文：https://www.cnblogs.com/setout/p/14529896.html