的Grails的MongoDB：保存圖值與域值失敗

Question

我有2個域類，用戶和狗（例如）

class User { 
    String id 
    Map<String, Dog> dogs 
} 

class Dog { 
    String name 
} 

我的控制器獲得作爲輸入的JSON

{"key" : "dogKey", "userId" : "someId", "dogName" : "dog"} 

def addDog(){ 
    String key = request.JSON.key 
    User user = User.get(request.JSON.userId) 
    String dogName = request.JSON.dog 
    ... 
    if(! user.dogs){ 
     user.dogs = new HashMap<>(1) 
    } 

    user.dogs.put(key, new Dog(name: dogName)) 
    user.save(flush: true) 
} 

後運行的用戶數據@蒙戈是：

用戶：

{ _id:...., 
    dogs: { 
     "dogKey": null 
    }... 
} 

有人能解釋我什麼我失蹤？

謝謝！

羅伊

Answer 1

可能是狗引用不是在數據庫

def addDog(){ 
     String key = request.JSON.key 
     User user = User.get(request.JSON.userId) 
     String dogName = request.JSON.dog 
     ... 
     if(! user.dogs){ 
      user.dogs = new HashMap<>(1) 
     } 
     Dog dog = new Dog(name: dogName) 
      dog.save(flush:true) 
     user.dogs.put(key, dog) 
     user.save(flush: true) 
    }