Jackson JSON
Spring 为 Jackson JSON 库提供支持。
JSON Views
Spring MVC 为 Jackson 的序列化视图 提供内置支持,它仅允许在 Object
中呈现所有字段的一个子集。要将它与 @ResponseBody
或 ResponseEntity
控制器方法结合使用,您可以使用 Jackson 的 @JsonView
注释激活序列化视图类,如下例所示:
-
Java
-
Kotlin
@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;
}
}
@RestController
class UserController {
@GetMapping("/user")
@JsonView(User.WithoutPasswordView::class)
fun getUser() = User("eric", "7!jd#h23")
}
class User(
@JsonView(WithoutPasswordView::class) val username: String,
@JsonView(WithPasswordView::class) val password: String) {
interface WithoutPasswordView
interface WithPasswordView : WithoutPasswordView
}
|
如果您希望以编程方式进行上述操作,而不是声明 @JsonView
注解,请使用 MappingJacksonValue
包装返回值并使用它来提供序列化视图:
-
Java
-
Kotlin
@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;
}
}
@RestController
class UserController {
@GetMapping("/user")
fun getUser(): MappingJacksonValue {
val value = MappingJacksonValue(User("eric", "7!jd#h23"))
value.serializationView = User.WithoutPasswordView::class.java
return value
}
}
对于依赖视图解析的控制器,您可以将序列化视图类添加到模型中,如下例所示:
-
Java
-
Kotlin
@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";
}
}
@Controller
class UserController : AbstractController() {
@GetMapping("/user")
fun getUser(model: Model): String {
model["user"] = User("eric", "7!jd#h23")
model[JsonView::class.qualifiedName] = User.WithoutPasswordView::class.java
return "userView"
}
}