There seems to be no special method, maybe I am not very talented,

The two methods I know:

map means that key-value pairs exist, so the types are It is fixed. We can apply for another map to traverse and replace the original map and convert it into a json string

String replacement, add double quotes using regular expressions: public?void?testJson() {

Map?map?=?new?HashMap();

map.put("aaa",?111);< /p>

String?json?=?JSON.toJSONString(map);

String?json1?=?json.replaceAll(":",?":\"");

json1?=?json1.replaceAll("}",?"\"}");

System.out.println(json);

System. out.println(json1);

}