杰克逊的JSON/XML根元素不一样

Question

首先，请注意我的问题非常类似于： Jackson xml and json root element 但只是略有不同，我只想为JSON使用单个根元素。

这里是我的UserList类：

@XmlRootElement(name = "users") 
@JsonRootName(value = "users") 
@JsonTypeName(value = "users") 
public class UserList { 

    // Tried all of these: 
    // @JacksonXmlElementWrapper(localName = "user") 
    // @JacksonXmlProperty(localName = "user") 
    // @JsonUnwrapped 
    // @JsonTypeInfo(include = JsonTypeInfo.As.WRAPPER_OBJECT, use = JsonTypeInfo.Id.NONE /**.NAME */) 
    // @JsonProperty("users") // <-- Sets both XML and JSON to 'users' 
    @JacksonXmlElementWrapper(useWrapping = false) // <-- This gets rid of duplicate 'users' in XML 
    public List<User> user = new ArrayList<User>(); 

    public UserList() {} 

} 

这里是我的用户等级：

@XmlRootElement(name = "user") 
@JsonRootName(value = "user") 
@JsonInclude(Include.NON_NULL) 
@XmlAccessorType(XmlAccessType.FIELD) 
public class User { 

    private int     userId; 
    private String    userName; 
    private String    password; 
    private long     passwordUpdated; 
    private long     passwordExpire; 
    private String    sessionKey; 

    public User() {} 

    getters and setters here ... 
} 

这是我所希望的JSON（目前我得到的“用户”而不是“用户”与当前测试代码）：

{ 
    "users": [{ 
    "userId": 1, 
    "userName": "test1@user.com", 
    "passwordUpdated": 0, 
    "passwordExpire": 0, 
    "sessionKey": "key" 
    }, { 
    "userId": 2, 
    "userName": "test2@user.com", 
    "passwordUpdated": 0, 
    "passwordExpire": 0, 
    "sessionKey": "key" 
    }] 
} 

这是我期望的XML（这是我用当前测试代码得到的）：

<?xml version="1.0" encoding="UTF-8"?> 
<users> 
    <user> 
    <userId>1</userId> 
    <userName>test1@user.com</userName> 
    <passwordUpdated>0</passwordUpdated> 
    <passwordExpire>0</passwordExpire> 
    <sessionKey>key</sessionKey> 
    </user> 
    <user> 
    <userId>2</userId> 
    <userName>test2@user.com</userName> 
    <passwordUpdated>0</passwordUpdated> 
    <passwordExpire>0</passwordExpire> 
    <sessionKey>key</sessionKey> 
    </user> 
</users> 

这里是我的测试代码：

{ 

    User user1 = new User(); 
    user1.setUserId(1); 
    user2.setUserName("test1@user.com"); 
    user1.setPasswordExpire(0); 
    user1.setPasswordUpdated(0); 
    user1.setSessionKey("key"); 

    User user2 = new User(); 
    user2.setUserId(1); 
    user2.setUserName("test2@user.com"); 
    user2.setPasswordExpire(0); 
    user2.setPasswordUpdated(0); 
    user2.setSessionKey("key"); 

    UserList userList = new UserList(); 
    userList.user.add(user1); 
    userList.user.add(user2); 

    String json = MapperUtils.modelToJson(userList); 

    String xml = MapperUtils.modelToXml(userList); 

} 

public class MapperUtils { 

    final static ObjectMapper jsonMapper = new ObjectMapper().configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false); 
    final static ObjectMapper xmlMapper = new XmlMapper().configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false); 

    public static String modelToJson(final Object object) throws IOException { 
    return jsonMapper.writeValueAsString(object); 
    } 

    public static String modelToXml(final Object object) throws IOException { 
    return xmlMapper.writer().writeValueAsString(object); 
    } 

} 

我的问题是，我想我的JSON的根元素是“用户”而不是“用户”。 任何帮助，将不胜感激。

Answer 1

@JacksonXmlProperty是如何在XML中重命名属性。然后让JSON的名称为下面我更改为users的字段名称。您也可以移除您尝试使用的大部分注释。这将产生预期的XML和JSON：

@JsonInclude(JsonInclude.Include.NON_NULL) 
@XmlAccessorType(XmlAccessType.FIELD) 
class User { 
    private int userId; 
    private String userName; 
    private String password; 
    private long passwordUpdated; 
    private long passwordExpire; 
    private String sessionKey; 
} 

@JsonRootName(value = "users") 
class UserList { 
    @JacksonXmlProperty(localName = "user") 
    @JacksonXmlElementWrapper(useWrapping = false) 
    List<User> users = new ArrayList<>(); 
}