Java8 stream toMap 解决 key 冲突

Map<Long, Integer> openStockProductSkuMap = openSkuStockList.stream()
    .collect(Collectors.toMap(
        BatchQueryProductStockListMpResponse::getProductSkuId,
        BatchQueryProductStockListMpResponse::getStockCount,
        (existing, replacement) -> replacement,
        HashMap::new
    ));