Spring MVC的@RequestBody收到非原始屬性

Question

對象包裝我創建JSON如下：

var manager = { 
     username: "admin", 
     password: "admin" 
    }; 
    var userToSubscribe = { 
     username: "newuser", 
     password: "newpassword", 
     email: "user@1and1.es" 
    }; 

    var openid = "myopenid"; 

    var subscription = { 
      manager: manager, 
      userToSubscribe : userToSubscribe, 
      openid : openid 
    }; 

    $.ajax({ 
     url: '/myapp/rest/subscribeUser.json', 
     type: 'POST', 
     dataType: 'json', 
     contentType: 'application/json', 
     mimeType: 'application/json', 
     data: JSON.stringify({subscription : subscription}) 
    }); 

這是發送的JSON：

{"subscription":{"manager":{"username":"admin","password":"admin"},"userToSubscribe":{"username":"newuser","password":"newpassword","email":"user@1and1.es"},"openid":"myopenid"}} 

，我想將這個JSON映射到一個Wrapper類。這是包裝：

private class Subscription{ 
    private User manager; 
    private User userToSubscribe; 
    private String openid; 
    public User getManager() { 
     return manager; 
    } 
    public void setManager(User manager) { 
     this.manager = manager; 
    } 
    public User getUserToSubscribe() { 
     return userToSubscribe; 
    } 
    public void setUserToSubscribe(User userToSubscribe) { 
     this.userToSubscribe = userToSubscribe; 
    } 
    public String getOpenid() { 
     return openid; 
    } 
    public void setOpenid(String openid) { 
     this.openid = openid; 
    } 
} 

傑克遜依賴性在pom.xml（我使用彈簧3.1.0.RELEASE）：

<dependency> 
     <groupId>org.codehaus.jackson</groupId> 
     <artifactId>jackson-mapper-asl</artifactId> 
     <version>1.9.10</version> 
    </dependency> 

在休息-servlet.xml中的映射

<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"> 
    <property name="messageConverters"> 
     <list> 
      <ref bean="jsonConverter" /> 
     </list> 
    </property> 
</bean> 

<bean id="jsonConverter" class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter"> 
    <property name="supportedMediaTypes" value="application/json" /> 
</bean> 

而控制器方法的報頭：

public @ResponseBody SimpleMessage subscribeUser(@RequestBody Subscription subscription) 

作爲POST的結果，我收到400錯誤的請求錯誤。是否有可能這樣做，或者我需要使用@RequestBody字符串還是@RequestBody Map<String,Object>來完成，並自己解碼JSON？

謝謝！

Answer 1

我要回答我自己的問題。首先要特別感謝Sotirios Delimanolis，因爲他給了我鑰匙，以便調查它發生了什麼。

如你所知，我從視圖中創建以下JSON：

{"manager":{"username":"admin","password":"admin"},"userToSubscribe":{"username":"newuser","password":"newpassword","email":"user@1and1.es"},"openid":"https://myopenid..."} 

我改變一點點，因爲我意識到這是沒有必要創建一個對象申購和一個變種訂閱。如果你建立這樣的JSON，這將很好地工作：

var manager = { 
    username: "admin", 
    password: "admin" 
}; 
var userToSubscribe = { 
    username: "newuser", 
    password: "newpassword", 
    email: "user@1and1.es" 
}; 

var openid = "https://myopenid..."; 

$.ajax({ 
    url: '/dp/rest/isUserSuscribed.json', 
    type: 'POST', 
    dataType: 'json', 
    contentType: 'application/json', 
    mimeType: 'application/json', 
    data: JSON.stringify({manager : manager, userToSubscribe : userToSubscribe, openid : openid}) 
}); 

控制器接收此JSON：

@RequestMapping(method=RequestMethod.POST, value="/isUserSuscribed.json") 
public @ResponseBody ResponseMessageElement<Boolean> isUserSuscribed(@RequestBody SubscriptionWrapper subscription){ 

而且SubscriptionWrapper ...

private static class SubscriptionWrapper { 
    BasicUser manager; 
    BasicUser userToSubscribe; 
    String openid; 

    public BasicUser getManager() { 
     return manager; 
    } 
    public void setManager(BasicUser manager) { 
     this.manager = manager; 
    } 
    public BasicUser getUserToSubscribe() { 
     return userToSubscribe; 
    } 
    public void setUserToSubscribe(BasicUser userToSubscribe) { 
     this.userToSubscribe = userToSubscribe; 
    } 
    public String getOpenid() { 
     return openid; 
    } 
    public void setOpenid(String openid) { 
     this.openid = openid; 
    } 
} 

所以...問題是什麼？我收到一個錯誤的請求400錯誤...我調試MappingJackson2HttpMessageConverter作爲Sotirios建議，並且有一個異常（沒有合適的構造函數）。傑克遜映射不能建立一個內部類，不管這個類是不是靜態的。將SubscriptionWrapper設置爲靜態是我的問題的解決方案。

您還可以查看這些問題的答案： http://stackoverflow.com/questions/8526333/jackson-error-no-suitable-constructor

http://stackoverflow.com/questions/12139380/how-to-convert-json-into-pojo-in-java-using-jackson

如果你有問題，反序列化，檢查： http://stackoverflow.com/questions/17400850/is-jackson-really-unable-to-deserialize-json-into-a-generic-type

感謝所有的答覆。

Answer 2

你不需要自己做。你需要在你的pom中添加這個依賴：

<dependencies> 
    <dependency> 
     <groupId>org.codehaus.jackson</groupId> 
     <artifactId>jackson-mapper-asl</artifactId> 
     <version>1.8.5</version> 
    </dependency> 
    </dependencies> 

之後，Spring會爲你做轉換。在你的JSON

{ 
    "subscription": { 
     "manager": { 
      "username": "admin", 
      "password": "admin" 
     }, 
     "userToSubscribe": { 
      "username": "newuser", 
      "password": "newpassword", 
      "email": "user@1and1.es" 
     }, 
     "openid": "myopenid" 
    } 
} 

根元素是subscription

Answer 3

看，這是一個JSON對象。您的Subscription類沒有subscription字段。因此沒有任何東西可以映射subscription元素，因此它會因400錯誤請求而失敗。

創建一個類SubscriptionWrapper

public class SubscriptionWrapper { 
    private Subscription subscription; 

    public Subscription getSubscription() { 
     return subscription; 
    } 

    public void setSubscription(Subscription subscription) { 
     this.subscription = subscription; 
    } 
} 

，改變你的處理方法來接受這種類型的參數

public @ResponseBody SimpleMessage subscribeUser(@RequestBody SubscriptionWrapper subscriptionWrapper) 

您可能需要配置ObjectMapper在MappingJacksonHttpMessageConverter（FYI，你應該使用MappingJackso2nHttpMessageConverter ），以便它忽略缺少的屬性。