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@@ -29,8 +29,18 @@ categories: 运维工具
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### list 对象根据某个字段分组
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-```java
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+``` java
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-Map<Object,List<Object>> map = demoList.stream().collect(Collectors.groupingBy(Object::getAttr));
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+ Map<Object,List<Object>> map = demoList.stream().collect(Collectors.groupingBy(Object::getAttr));
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```
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+
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+### list用stream进行排序
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+
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+``` java
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+ //根据单个属性排序
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+ List<String> stortList = list.stream().sorted().collect(Collectors.toList());
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+ //根据对象某个属性排序
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+ List<Object> sortList = objectList.stream().sorted(Comparator.comparing(Object::getAttr).reversed()).collect(Collectors.toList());
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+
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+```
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