解析JSONObject并将动态键/值插入到数据库中

Question

如何从JSONObject中将动态键值插入到数据库中。

我能够从发布请求中提取关键值并单独输出，但我无法管理它将它们存储在数据库中。

@POST 
@Path("/user") 
@Produces(MediaType.APPLICATION_JSON) 
@Consumes(MediaType.APPLICATION_JSON) 
public String keyValueFromJson(String userFormData) throws JSONException { 

    PreparedStatement query = null; 
    Connection conn = null; 

    JSONObject jsOb = new JSONObject(userFormData); 
    JSONArray jaArr = jsOb.getJSONArray("formData"); 

    try { 

     conn = DaoMessenger.PostGresCon().getConnection(); 

     for (int i = 0; i < jaArr.length();) { 
      JSONObject jsonObject = jaArr.getJSONObject(i); 
      Iterator<String> keys = jsonObject.keys(); 
      while (keys.hasNext()) { 
       String key = keys.next(); 
       Object value = jsonObject.get(key); 
       System.out.println(key + ": " + value); 
       query = conn.prepareStatement ("INSERT INTO users (" + key + ") values(" + value + ")"); 
       ResultSet rs = query.executeQuery(); 
      } 

      i++; 
     } 

    } catch (Exception e){ 
     e.printStackTrace(); 
    } 

    return userFormData; 
} 

JSON对象经由客户端发送带有角：

{ 
"formData": 
[ 
    { 
     "id":235, 
     "username":"john", 
     "enabled":"true", 
     "last_login":"2017-03-03 19:49:56", 
     "pass":"xxxxx" 

    } 
] 
} 

数据库是Postgres的9.6.1

错误（堆栈跟踪）：

org.postgresql.util.PSQLException: ERROR: column "xxxxx" does not exist 
Position: 34 

我有一个逻辑while循环中的错误，但我无法弄清楚。

Answer 1

我做了一些变化，它的工作原理是这样的：

StringBuilder sbv = new StringBuilder(); 
StringBuilder sbk = new StringBuilder(); 
String prefix = ""; 

    try { 
     conn = DaoMessenger.PostGresCon().getConnection(); 
     for (int i = 0; i < jaArr.length();) { 
      JSONObject jsonObject = jaArr.getJSONObject(i); 
      Iterator<String> keys = jsonObject.keys(); 

      while (keys.hasNext()) { 
       String key = keys.next(); 
       Object value = jsonObject.get(key); 
       sbk.append(prefix); 
       sbv.append(prefix); 
       prefix = ","; 
       sbv.append("'").append(value).append("'"); 
       sbk.append(key); 
      } 
      query = conn.prepareStatement("INSERT INTO users (" + sbk.toString() + ") values (" + sbv.toString() + ")"); 
      ResultSet rs = query.executeQuery(); 

      i++; 
     } 

    } catch (Exception e){ 
     e.printStackTrace(); 
    }