Android自己写一个简单的Json转实体类的小框架——基于Java反射

Android自己写一个简单的Json转实体类的小框架

1.假设有如下Json

String json1 = "[{\"albumId\": 1,\"id\": 1,\"title\": \"accusamus beatae ad facilis cum similique qui sunt\",\"url\": \"https://via.placeholder.com/600/92c952\",\"thumbnailUrl\": \"https://via.placeholder.com/150/92c952\"},{\"albumId\": 1,\"id\": 2,\"title\": \"reprehenderit est deserunt velit ipsam\",\"url\": \"https://via.placeholder.com/600/771796\",\"thumbnailUrl\": \"https://via.placeholder.com/150/771796\"}]";

2.新建对应的Java实体类

public class Album {

    private int albumId;
    private int id;
    private String title;
    private String url;
    private String thumbnailUrl;


    public Album(int albumId, int id, String title, String url, String thumbnailUrl) {
        this.albumId = albumId;
        this.id = id;
        this.title = title;
        this.url = url;
        this.thumbnailUrl = thumbnailUrl;
    }
    
    

    public Album() {
    }

    public int getAlbumId() {
        return albumId;
    }

    public void setAlbumId(int albumId) {
        this.albumId = albumId;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getUrl() {
        return url;
    }

    public void setUrl(String url) {
        this.url = url;
    }

    public String getThumbnailUrl() {
        return thumbnailUrl;
    }

    public void setThumbnailUrl(String thumbnailUrl) {
        this.thumbnailUrl = thumbnailUrl;
    }
}

3.由于这是一个Json数组，所以方法只针对于Json数组，大家可以根据需求自行改动

    private <T> List<T> JsonToListObject(String json,Class<T> tClass) throws Exception
    {
        JSONArray array = new JSONArray(json);
        List<T> TList = new ArrayList<>();
        for (int i = 0; i < array.length(); i++) {
            JSONObject jsonObject = new JSONObject(array.optString(i));
            T t = tClass.getDeclaredConstructor().newInstance();
            Iterator<String> keys = jsonObject.keys();
            while (keys.hasNext())
            {
                String key = keys.next();
                Field field = tClass.getDeclaredField(key);
                field.setAccessible(true);
                //以此用反射出来的field字段判断该属性类型
                if (field.getType().equals(int.class))
                {
                    field.set(t,jsonObject.optInt(key));
                }
                if (field.getType().equals(String.class))
                {
                    field.set(t,jsonObject.optString(key));
                }
                //......后续可以根据需求自行添加
            }
            TList.add(t);

        }
        return TList;
    }

4.最后在需要的地方进行调用

  try {
                  List<Album> albums = JsonToListObject(json1, Album.class);
                    System.out.println(albums);
                } catch (Exception e) {
                    e.printStackTrace();
                }