Spring boot @ResponseBody doesn't serialize entity id

Question

Have a strange problem and can't figure out how to deal with it. Have simple POJO:

@Entity
@Table(name = "persons")
public class Person {

    @Id
    @GeneratedValue
    private Long id;

    @Column(name = "first_name")
    private String firstName;

    @Column(name = "middle_name")
    private String middleName;

    @Column(name = "last_name")
    private String lastName;

    @Column(name = "comment")
    private String comment;

    @Column(name = "created")
    private Date created;

    @Column(name = "updated")
    private Date updated;

    @PrePersist
    protected void onCreate() {
        created = new Date();
    }

    @PreUpdate
    protected void onUpdate() {
        updated = new Date();
    }

    @Valid
    @OrderBy("id")
    @OneToMany(mappedBy = "person", fetch = FetchType.EAGER, cascade = CascadeType.ALL, orphanRemoval = true)
    private List<PhoneNumber> phoneNumbers = new ArrayList<>();

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getMiddleName() {
        return middleName;
    }

    public void setMiddleName(String middleName) {
        this.middleName = middleName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public String getComment() {
        return comment;
    }

    public void setComment(String comment) {
        this.comment = comment;
    }

    public Date getCreated() {
        return created;
    }

    public Date getUpdated() {
        return updated;
    }

    public List<PhoneNumber> getPhoneNumbers() {
        return phoneNumbers;
    }

    public void addPhoneNumber(PhoneNumber number) {
        number.setPerson(this);
        phoneNumbers.add(number);
    }

    @Override
    public String toString() {
        return ToStringBuilder.reflectionToString(this, ToStringStyle.SHORT_PREFIX_STYLE);
    }
}

@Entity
@Table(name = "phone_numbers")
public class PhoneNumber {

    public PhoneNumber() {}

    public PhoneNumber(String phoneNumber) {
        this.phoneNumber = phoneNumber;
    }

    @Id
    @GeneratedValue
    private Long id;

    @Column(name = "phone_number")
    private String phoneNumber;

    @ManyToOne
    @JoinColumn(name = "person_id")
    private Person person;

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getPhoneNumber() {
        return phoneNumber;
    }

    public void setPhoneNumber(String phoneNumber) {
        this.phoneNumber = phoneNumber;
    }

    public Person getPerson() {
        return person;
    }

    public void setPerson(Person person) {
        this.person = person;
    }

    @Override
    public String toString() {
        return ToStringBuilder.reflectionToString(this, ToStringStyle.SHORT_PREFIX_STYLE);
    }
}

and rest endpoint:

@ResponseBody
@RequestMapping(method = RequestMethod.GET)
public List<Person> listPersons() {
    return personService.findAll();
}

In json response there are all fields except Id, which I need on front end side to edit/delete person. How can I configure spring boot to serialize Id as well?

That's how response looks like now:

[{
  "firstName": "Just",
  "middleName": "Test",
  "lastName": "Name",
  "comment": "Just a comment",
  "created": 1405774380410,
  "updated": null,
  "phoneNumbers": [{
    "phoneNumber": "74575754757"
  }, {
    "phoneNumber": "575757547"
  }, {
    "phoneNumber": "57547547547"
  }]
}]

UPD Have bidirectional hibernate mapping, maybe it's somehow related to issue.

Could you please give us more insights about your spring setup? What json marshaller do you use? The default one, jackson, ...? — Ota
Actually there is no special setup. Wanted to try out spring boot :) Added spring-boot-starter-data-rest to pom and using @EnableAutoConfiguration that's all. Read couple of tutorials and seems like all have to work out of the box. And it is, except that Id field. Updated post with endpoint response. — Konstantin
In Spring 4 you should also use @RestController on controller class and remove @ResponseBody from methods. Also I would suggest having DTO classes to handle json requests/responses instead of domain objects. — Vaelyr

Patrick Grimard Patrick Grimard · Accepted Answer · 2014-07-31T18:41:06

I recently had the same problem and it's because that's how spring-boot-starter-data-rest works by default. See my SO question -> While using Spring Data Rest after migrating an app to Spring Boot, I have observed that entity properties with @Id are no longer marshalled to JSON

To customize how it behaves, you can extend RepositoryRestConfigurerAdapter to expose IDs for specific classes.

import org.springframework.context.annotation.Configuration;
import org.springframework.data.rest.core.config.RepositoryRestConfiguration;
import org.springframework.data.rest.webmvc.config.RepositoryRestConfigurerAdapter;

@Configuration
public class RepositoryConfig extends RepositoryRestConfigurerAdapter {
    @Override
    public void configureRepositoryRestConfiguration(RepositoryRestConfiguration config) {
        config.exposeIdsFor(Person.class);
    }
}

Spring boot @ResponseBody doesn't serialize entity id

9 Answers