首页 Map<String, List<CoreSpaceExcelBo>> map = all.stream().collect(Collectors.groupingBy(p -> p.getSpaceCode()+ "#" + p.getItemCode() + "#" + p.getCartonCode()));根据 CoreSpaceExcelBo对象的CartonCode字段去重，累加CoreSpaceExcelBo中的num字段

Map<String, List<CoreSpaceExcelBo>> map = all.stream().collect(Collectors.groupingBy(p -> p.getSpaceCode()+ "#" + p.getItemCode() + "#" + p.getCartonCode()));根据 CoreSpaceExcelBo对象的CartonCode字段去重，累加CoreSpaceExcelBo中的num字段

时间: 2023-05-26 18:05:23 浏览: 123

Java中 List《map》把里面map中某个key相同记录的其他key 的 value 合并

Java中 List《map》把里面map中某个key相同记录的其他key 的 value 合并 Java中 List《map》把里面map中某个key相同记录的其他key 的 value 合并

这段代码的作用是将一个名为all的列表按照其中元素的SpaceCode属性进行分组，并将分组后的结果保存在一个Map中，其中键值是字符串类型的SpaceCode属性值，值是一个CoreSpaceExcelBo类型的列表。

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