Java Json的各种处理
一、net.sf.json
1、Json转Map
JSONObject jsonObject = JSONObject.fromObject(jsonStr);
Map<String,Object> map = new HashMap<>();
map.put("code",jsonObject .getInt("code"));2、Json转实体
JSONObject jsonObject = JSONObject.fromObject(jsonStr); ArticleForm articleForm = (ArticleForm) JSONObject.toBean(jsonObject , ArticleForm.class);
如果实体中带有List字段，需要指定泛型
Map<String, Class> classMap = new HashMap<String, Class>();
classMap.put("keywords", String.class);
ArticleForm articleForm = (ArticleForm) JSONObject.toBean(data.getJSONObject(i), ArticleForm.class,classMap);3、Json转集合
List<ArticleForm> list = new ArrayList<>();
JSONArray data = jsonObject.getJSONArray("data");
if (errorCode == 0 && data != null && !data.isEmpty()) {
for (int i = 0; i < data.size(); i ) {
Map<String, Class> classMap = new HashMap<String, Class>();
classMap.put("keywords", String.class);
ArticleForm articleForm = (ArticleForm) JSONObject.toBean(data.getJSONObject(i), ArticleForm.class,classMap);
list.add(articleForm);
}
}另外一种：
List<ArticleForm> list = new ArrayList<>();
JSONArray data = jsonObject.getJSONArray("data");
if (errorCode == 0 && data != null && !data.isEmpty()) {
Map<String, Class> classMap = new HashMap<String, Class>();
classMap.put("keywords", String.class);
list = (List<ArticleForm>) JSONArray.toArray(data, ArticleForm.class,classMap);
}二、com.alibaba.fastjson
1、Json转Map
JSONObject jsonObject = JSON.parseObject(jsonStr);
Map<String,Object> map = new HashMap<>();
map.put("code",jsonObject .getInt("code"));2、Json转实体
ArticleForm articleForm = JSON.parseObject(jsonStr, new TypeReference<ArticleForm>() {});3、Json转集合
List<ArticleForm> list = JSON.parseObject(jsonStr,new TypeReference<ArrayList<ArticleForm>>() {});Java常用json处理
// 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<Object>或者object
String str1 = "[\"总分\",\"语文\",\"数学\",\"英语\",\"道德与法治\",\"科学基础\"]";
List<String> list = JSON.parseArray(str1, String.class); // json转list集合，将String.class改成其他对象.class即可
System.out.println("list:" JSON.toJSONString(list));
String s1 = JSON.parseObject(JSON.toJSONString("语文"), String.class); // json转对象，将String.class改成其他对象.class即可
System.out.println("s1:" s1);
// object转字符串后即可转jsonObject或者jsonArray
// json和map
Map<String, Object> map = new HashMap<>();
map.put("xAxis","11");
map.put("yAxis","2222");
String json = JSON.toJSONString(map);//map转String
System.out.println("json:" json);
Map<String, Object> map1 = JSON.parseObject(json, Map.class); // 转List<Map> parserArray即可
System.out.println("map1:" map1);以上为个人经验，希望能给大家一个参考，也希望大家多多支持Devmax。