What are the processing methods of Json in Java?-javaTutorial-php.cn

Various processing of Java Json

1. net.sf.json

1. Json to Map

JSONObject jsonObject = JSONObject.fromObject(jsonStr); Map map = new HashMap<>(); map.put("code",jsonObject .getInt("code"));

Copy after login

2. Convert Json to entity

JSONObject jsonObject = JSONObject.fromObject(jsonStr); ArticleForm articleForm = (ArticleForm) JSONObject.toBean(jsonObject , ArticleForm.class);

Copy after login

If the entity has a List field, you need to specify the generic type

Map classMap = new HashMap(); classMap.put("keywords", String.class); ArticleForm articleForm = (ArticleForm) JSONObject.toBean(data.getJSONObject(i), ArticleForm.class,classMap);

Copy after login

3. Convert Json to collection

List list = new ArrayList<>(); JSONArray data = jsonObject.getJSONArray("data"); if (errorCode == 0 && data != null && !data.isEmpty()) { for (int i = 0; i < data.size(); i++) { Map classMap = new HashMap(); classMap.put("keywords", String.class); ArticleForm articleForm = (ArticleForm) JSONObject.toBean(data.getJSONObject(i), ArticleForm.class,classMap); list.add(articleForm); } }

Copy after login

Another one:

List list = new ArrayList<>(); JSONArray data = jsonObject.getJSONArray("data"); if (errorCode == 0 && data != null && !data.isEmpty()) { Map classMap = new HashMap(); classMap.put("keywords", String.class); list = (List) JSONArray.toArray(data, ArticleForm.class,classMap); }

Copy after login

2. com.alibaba.fastjson

1. Convert Json to Map

JSONObject jsonObject = JSON.parseObject(jsonStr); Map map = new HashMap<>(); map.put("code",jsonObject .getInt("code"));

Copy after login

2. Convert Json to entity

ArticleForm articleForm = JSON.parseObject(jsonStr, new TypeReference() {});

Copy after login

3. Convert Json to collection

List list = JSON.parseObject(jsonStr,new TypeReference>() {});

Copy after login

Java commonly used json processing

// String和json的互相转换 String str = "{\"status\":200,\"message\":\"\",\"data\":{\"KmList\":[\"总分\",\"语文\",\"数学\",\"英语\",\"道德与法治\",\"科学基础\"]}}"; System.out.println("str:"+str); // JSONArray arrays = JSON.parseArray(str); // string转jsonArray JSONObject jsonObject = JSON.parseObject(str); // string转jsonObject System.out.println("jsonObject:"+jsonObject); String s = jsonObject.toJSONString(); // json（object和Array相同）转string // json转list