java中Map List的用法_定义map

返回的restful接口数据样式：

{
     party: [
         {
             "finishTime": "20191105",
             "busiCnt": 1000
         }
     ]
 }
1
2
3
4
5
6
7
8

1、定义WzwScreenEntity 实体

public class WzwScreenEntity {

    private String finishTime;
    private String busiCnt;
    private String party;

    public String getFinishTime() {
        return finishTime;
    }

    public void setFinishTime(String finishTime) {
        this.finishTime = finishTime;
    }

    public String getBusiCnt() {
        return busiCnt;
    }

    public void setBusiCnt(String busiCnt) {
        this.busiCnt = busiCnt;
    }

    public String getParty() {
        return party;
    }

    public void setParty(String party) {
        this.party = party;
    }
}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30

2、定义list实体

public class WzwScreenChildEntity {
    public String getFinishTime() {
        return finishTime;
    }

    public void setFinishTime(String finishTime) {
        this.finishTime = finishTime;
    }

    public String getBusiCnt() {
        return busiCnt;
    }

    public void setBusiCnt(String busiCnt) {
        this.busiCnt = busiCnt;
    }

    private String finishTime;
    private String busiCnt;
}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20

3、具体实现

List<WzwScreenEntity> scList = new ArrayList<>();
scList  = mapper.queryData();//从数据库获取数据
Map<String, List> map = new HashMap<>();//定义返回的map

if (scList.size() != 0) {
    for (WzwScreenEntity entity : scList) {
        WzwScreenChildEntity childEntity = new WzwScreenChildEntity();
        childEntity.setFinishTime(entity.getFinishTime());
        childEntity.setBusiCnt(entity.getBusiCnt());

        List<WzwScreenChildEntity> list = new ArrayList<>();
        list.add(childEntity);

		//当map中的key相同的，防止value值被覆盖。
        if (map.containsKey(entity.getParty())) {
            list.addAll(map.get(entity.getParty()));
            map.put(entity.getParty(), list);
        } else {
            map.put(entity.getParty(), list);
        }
    }
}
LOGGER.info("map================== " + map);
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23