public static void main(String[] args) {
Map<String, Integer> map = new HashMap<>();
map.put("id", 4);
map.put("name", 1);
map.put("sex", 3);
map.put("age", 2);
//根据value正序
Map<String, Integer> result1 = map.entrySet().stream().
sorted(Map.Entry.comparingByValue())
.collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue,
(oldValue, newValue) -> oldValue, LinkedHashMap::new));
//根据value倒序
Map<String, Integer> result2 = map.entrySet().stream().
sorted(Map.Entry.comparingByValue(Comparator.reverseOrder()))
.collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue,
(oldValue, newValue) -> oldValue, LinkedHashMap::new));
//根据key正序
Map<String, Integer> result3 = map.entrySet().stream().
sorted(Map.Entry.comparingByKey())
.collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue,
(oldValue, newValue) -> oldValue, LinkedHashMap::new));
//根据key倒序
Map<String, Integer> result4 = map.entrySet().stream().
sorted(Map.Entry.comparingByKey(Comparator.reverseOrder()))
.collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue,
(oldValue, newValue) -> oldValue, LinkedHashMap::new));
System.out.println(result1);
System.out.println(result2);
System.out.println(result3);
System.out.println(result4);
}
输出结果
{name=1, age=2, sex=3, id=4}
{id=4, sex=3, age=2, name=1}
{age=2, id=4, name=1, sex=3}
{sex=3, name=1, id=4, age=2}