LinkedHashMap<Integer, List<CarsDBBasicTrim>> carsDBBasicTrimMap =
carsDBBasicTrimList.stream().collect(Collectors.groupingBy(CarsDBBasicTrim::getYear, LinkedHashMap::new, Collectors.toList()));
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Java基础 Map集合框架 LinkedHashMap
Java基础 Map集合框架 LinkedHashMap
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