Java中list里面存放map,根据map中的某一个字段进行排序
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2022-07-10 21:15:29
package com.example.demo;import java.util.ArrayList;import java.util.Collections;import java.util.Comparator;import java.util.HashMap;import java.util.List;import java.util.Map;/** * *
* Description: *
* * @author xu....
package com.example.demo;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
*
* <p>
* Description:
* </p>
*
* @author xuyangwei
*
* @date 2020年7月15日
*
*/
public class SortListMap {
/**
* @param args
*/
public static void main(String[] args) {
List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();
Map<String, Object> map1 = new HashMap<String, Object>();
map1.put("id", "1");
map1.put("name", "jack");
Map<String, Object> map2 = new HashMap<String, Object>();
map2.put("id", "2");
map2.put("name", "tom");
Map<String, Object> map3 = new HashMap<String, Object>();
map3.put("id", "3");
map3.put("name", "marry");
list.add(map1);
list.add(map3);
list.add(map2);
// 排序前
for (Map<String, Object> map : list) {
System.out.println(map.get("id"));
}
Collections.sort(list, new Comparator<Map<String, Object>>() {
public int compare(Map<String, Object> o1, Map<String, Object> o2) {
String id1 = (String) o1.get("id");
String id2 = (String) o2.get("id");
return id1.compareTo(id2);
}
});
// 排序后
System.out.println("-------------------");
for (Map<String, Object> map : list) {
System.out.println(map.get("id"));
}
}
}
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