How to return a ManyToOne Bidirectional JPA Entity Object in response of a Spring RestController?-CodePudding

I have 2 entities User and Authority having bidirectional Many-To-One relationship b/w them. But when I send the User object as a response from the RestController, I get nested objects ie. User{Authority{User{Authority{User{Authority{..}}}}}}

How can I achieve that the controller must return only? User{Authority{}}

Below is my User entity class :-

@Entity
public class User {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long userId;

    private String username;
    private String password;
    private String mobileNo;

    @OneToMany(fetch =FetchType.EAGER , cascade = CascadeType.ALL, mappedBy = "user")
    private Set<Authorities> authorities;
    
    // non-parameterized and parameterized constructor and all getters and setters 

}

@Entity
public class Authorities implements GrantedAuthority {

    private static final long serialVersionUID = -2789840366318513805L;
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    private String authority;

    @ManyToOne
    private User user;

    // non-parameterized and parameterized constructor and all getters and setters 
}

@RestController
public class HomeController {
    
    @GetMapping(path = "/home")
    public @ResponseBody User home(@AuthenticationPrincipal User user){
        return user;
    } 
}

Below is the snippet from my browser:

    at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:728) ~[jackson-databind-2.12.4.jar:2.12.4]
    at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:770) ~[jackson-databind-2.12.4.jar:2.12.4]
    at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:178) ~[jackson-databind-2.12.4.jar:2.12.4]
    at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:728) ~[jackson-databind-2.12.4.jar:2.12.4]
    at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:770) ~[jackson-databind-2.12.4.jar:2.12.4]
    at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:178) ~[jackson-databind-2.12.4.jar:2.12.4]
    at com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serializeContents(CollectionSerializer.java:145) ~[jackson-databind-2.12.4.jar:2.12.4]
    at com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serialize(CollectionSerializer.java:107) ~[jackson-databind-2.12.4.jar:2.12.4]
    at com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serialize(CollectionSerializer.java:25) ~[jackson-databind-2.12.4.jar:2.12.4]
    at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:728) ~[jackson-databind-2.12.4.jar:2.12.4]
    at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:770) ~[jackson-databind-2.12.4.jar:2.12.4]
    at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:178) ~[jackson-databind-2.12.4.jar:2.12.4]
    at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:728) ~[jackson-databind-2.12.4.jar:2.12.4]
    at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:770) ~[jackson-databind-2.12.4.jar:2.12.4]
    at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:178) ~[jackson-databind-2.12.4.jar:2.12.4]
    at com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serializeContents(CollectionSerializer.java:145) ~[jackson-databind-2.12.4.jar:2.12.4]
    at com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serialize(CollectionSerializer.java:107) ~[jackson-databind-2.12.4.jar:2.12.4]
    at com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serialize(CollectionSerializer.java:25) ~[jackson-databind-2.12.4.jar:2.12.4]
    at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:728) ~[jackson-databind-2.12.4.jar:2.12.4]
    at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:770) ~[jackson-databind-2.12.4.jar:2.12.4]

2021-09-18 00:45:17.935 ERROR 9340 --- [nio-8080-exec-7] s.e.ErrorMvcAutoConfiguration$StaticView : Cannot render error page for request [/home] as the response has already been committed. As a result, the response may have the wrong status code.

CodePudding user response：

in Authorities class add @JsonIgnore above the User field

@ManyToOne
@JsonIgnore
private User user;