如何将 JSON 对象转换为 DBObject？

Question

我有一个 JSON 对象 obj，我想将它存储到 MongoDB 中：JSONObject obj = new JSONObject();obj.put("title", obj1.title);//For rules:Map m = new LinkedHashMap();// for rules, first create JSONArray  JSONArray ja = new JSONArray(); m = new LinkedHashMap();m.put("right_connective", "&&");m.put("attribute", "amount");m.put("operator", "<=");m.put("value", obj1.amount);m.put("rank", 1);m.put("encapsulated", "false");ja.add(m);m = new LinkedHashMap();m.put("left_connective", "&&");m.put("right_connective", "&&");m.put("attribute", "project");m.put("operator", "==");m.put("value", obj1.project);m.put("rank", 2);m.put("encapsulated", "false");ja.add(m);m = new LinkedHashMap();m.put("left_connective", "&&");m.put("right_connective", "&&");m.put("attribute", "type");m.put("operator", "==");m.put("value", obj1.type);m.put("rank", 3);m.put("encapsulated", "false");ja.add(m);m = new LinkedHashMap();m.put("left_connective", "&&");m.put("attribute", "car");m.put("operator", "==");m.put("value", obj1.car);m.put("rank", 4);m.put("encapsulated", "false");ja.add(m);obj.put("rule", ja);Document doc = Document.parse( obj.toString() );BasicDBObject dbObject = mapper.readValue(obj, BasicDBObject.class);collection.insert(dbObject);我收到“映射器无法解析为类型”的错误。我需要包含哪个导入语句？否则，你能建议替代方法吗？我不想走 MongoDocument 路线，因为 insertOne() 函数在写入数据库时跳过了一些文档。

Answer 1

如果您正在使用，则不需要映射器org.json.JSONObject：

 DBObject object = (DBObject) JSON.parse(obj.toString());

 collection.insert(object)

Answer 2

我相信您正在使用如下所示的 jackson.Create ObjectMapper 来解决“映射器无法解析为类型”

import com.fasterxml.jackson.databind.ObjectMapper; //import statement

ObjectMapper mapper = new ObjectMapper(); //initialization