傑克遜數據綁定時如何獲取Pojo名稱引用的Json對象

Question

我正在使用Jackson生成Rest Services。 我能夠得到像

[{"userName":"scott","userId":7},{"userName":"toe","userId":101}]

但我期望Pojo名稱的響應指向如下所示的響應

{"UserDetails":[{"userName":"scott","userId":7},{"userName":"toe","userId":101}]}

這是我的實現類

@Service("userServices")
public class UserServiceImpl implements UserServices{

private UserServices userServices;

public UserServices getUserServices() {
    return userServices;
}
public void setUserServices(UserServices userServices) {
    this.userServices = userServices;
}

@Override
public List<UserDetails> getUser(UserDetails userDetails) {


    ObjectMapper mapper = new ObjectMapper();

    List<UserDetails> user = new ArrayList<UserDetails>();
    List<UserDetails> list = new ArrayList<UserDetails>();

    UserDetails userDetails2 = new UserDetails();
    userDetails2.setUserName("scott");
    userDetails2.setUserId(007);

    UserDetails userDetails3 = new UserDetails();
    userDetails3.setUserName("toe");
    userDetails3.setUserId(101);

    user.add(userDetails2);
    user.add(userDetails3);

    try{
    String jsonString = mapper.writeValueAsString(user);
    UserDetails[] userDetails4 = mapper.readValue(jsonString, UserDetails[].class);
    list = Arrays.asList(userDetails4);
    System.out.println(userDetails4);
    }catch (Exception e) {
        System.out.println(e);
    }
    return list;
}
}

這是我的pojo

public class UserDetails implements Serializable{

private String userName;
private int userId;

public UserDetails(){

}

 //getters and setters...
}

**注意：**我不想在域對象端使用任何注釋。

Answer 1

剛回來

UserDetailsResponse：

public class UserDetailsResponse {

    private List<UserDetails> userDetails;
    // getter and setter

}

而不是UserServiceImpl中的UserDetails列表（大概是在控制器中）。

Answer 2

您返回一個UserDetails列表，該列表轉換為響應對象，即JSON數組。 為了獲得所需的結果，您需要創建一個Container類（UserDetailsContainer），該類具有List類型的屬性userDetails並返回其實例作為響應。

Answer 3

您可以使用objectMapper.writeValueAsString(aCustomMap)創建自定義json視圖。

例：

UserDetails userDetails2 = new UserDetails();
userDetails2.setUserName("scott");
userDetails2.setUserId(007);

UserDetails userDetails3 = new UserDetails();
userDetails3.setUserName("toe");
userDetails3.setUserId(101);

Map<String, List<UserDetails>> m = new HashMap<>();
m.put("UserDetails", Arrays.asList(userDetails2, userDetails3));

System.out.print(
    //This is what you need
    objectMapper.writeValueAsString(m)
);
//{"UserDetails":[{"userName":"scott","userId":7},{"userName":"toe","userId":101}]}