Jackson JSON

Infra offers support for the Jackson JSON library.

JSON Views

Web MVC provides built-in support for Jackson’s Serialization Views, which allow rendering only a subset of all fields in an Object. To use it with @ResponseBody or ResponseEntity controller methods, you can use Jackson’s @JsonView annotation to activate a serialization view class, as the following example shows:

Java

@RestController
public class UserController {

  @GetMapping("/user")
  @JsonView(User.WithoutPasswordView.class)
  public User getUser() {
    return new User("eric", "7!jd#h23");
  }
}

public class User {

  public interface WithoutPasswordView {};
  public interface WithPasswordView extends WithoutPasswordView {};

  private String username;
  private String password;

  public User() {
  }

  public User(String username, String password) {
    this.username = username;
    this.password = password;
  }

  @JsonView(WithoutPasswordView.class)
  public String getUsername() {
    return this.username;
  }

  @JsonView(WithPasswordView.class)
  public String getPassword() {
    return this.password;
  }
}

@JsonView allows an array of view classes, but you can specify only one per controller method. If you need to activate multiple views, you can use a composite interface.

If you want to do the above programmatically, instead of declaring an @JsonView annotation, wrap the return value with MappingJacksonValue and use it to supply the serialization view:

Java

@RestController
public class UserController {

  @GetMapping("/user")
  public MappingJacksonValue getUser() {
    User user = new User("eric", "7!jd#h23");
    MappingJacksonValue value = new MappingJacksonValue(user);
    value.setSerializationView(User.WithoutPasswordView.class);
    return value;
  }
}

For controllers that rely on view resolution, you can add the serialization view class to the model, as the following example shows:

Java

@Controller
public class UserController extends AbstractController {

  @GetMapping("/user")
  public String getUser(Model model) {
    model.addAttribute("user", new User("eric", "7!jd#h23"));
    model.addAttribute(JsonView.class.getName(), User.WithoutPasswordView.class);
    return "userView";
  }
}