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ManyToOne referenced entities not exist in JSON Response when returning PagedResource

When I return a Page<Entity> from a method inside my @RestController class, all fields of Entity both referenced via @OneToXXX and @ManyToXXX take place in the returned JSON object. But when I switched the return type to PagedResource (to be able to add links to the response), @ManyToXXX fields are not included at all.

Page<Entity>

@RestController

Entity

@OneToXXX

@ManyToXXX

PagedResource

@ManyToXXX

Here is the method in question:

@GetMapping("/fetch")
public PagedResources getResults(Pageable pageable, PagedResourcesAssembler assembler) {

Page<ParentClass> page = myRepository.findAll(pageable);

PagedResources pagedResources = assembler.toResource(page, myResourceAssembler);

return pagedResources;
}


Here are the basic class definitions:

ParentClass

@Entity
@Table(name = "parent_table", catalog = "myDB")
public class ParentClass implements Serializable {

private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "id", nullable = false)
private Integer id;

@ManyToOne(optional = false)
@JoinColumn(name = "other_class", referencedColumnName = "id")
private OtherClass otherClass;

@OneToOne(mappedBy = "parent")
private SampleField1 sampleField1;

@OneToMany(mappedBy = "parent")
private List<SampleField2> sampleField2;

}


SampleField1 OneToXXX

@Entity
@Table(name = "sample_table_1", catalog = "myDB")
public class SampleField1 implements Serializable {

private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "id", nullable = false)
private Integer id;

@Column(name="some_field")
String someField;

@OneToOne
@JoinColumn(name = "sample_field_1", referencedColumnName = "id")
@JsonBackReference //to avoid infinite recursion
private ParentClass parent;
}


OtherClass ManyToOne

@Entity
@Table(name = "other_table", catalog = "myDB")
public class OtherClass implements Serializable {

private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "id", nullable = false)
private Integer id;

@Column(name="some_other_field")
String someOtherField;

// I don't need any reference to ParentClass here.
}


To add further detail to the issue here is the logging output of changeProperties() method inside PersistentEntityJackson2Module class:

changeProperties()

PersistentEntityJackson2Module

s.d.r.w.j.PersistentEntityJackson2Module : Assigning nested entity serializer for @javax.persistence.OneToOne(..) com.project.SampleField1 com.project.model.ParentClass.sampleField1
s.d.r.w.j.PersistentEntityJackson2Module : Assigning nested entity serializer for @javax.persistence.OneToMany(..) com.project.SampleField2 com.project.model.ParentClass.sampleField2
// .... omitted other lines for brevity


the resulting JSON is :

{
"_embedded":{
"parentClasses":[
{
"id":1,
// <-- There is no field for otherClass !
"sampleField1":{
"id":1,
"sampleField":"blabla"
},
"sampleField2":[ ]
}
]
},
"links":[

]
}


As it can be seen above, OneToXXX fields are being taken to be serialized but no output for the ManyToOne fields like
Assigning nested entity serializer for @javax.persistence.ManyToOne ... com.my.OtherClass ... and therefore those aren't existed in the response JSON.

OneToXXX

ManyToOne

Assigning nested entity serializer for @javax.persistence.ManyToOne ... com.my.OtherClass ...

According to this SO answer, @ManyToXXX referenced entities are appended as links to the JSON response. But that's not an acceptable solution for me since I have a different planning of consumption in my mind for the rest client.

@ManyToXXX

Bottomline, I'd like to have my ManyToOne referenced entities in my JSON Response returned from getResults() method.

ManyToOne

getResults()

Anything I can provide just ask in the comments.

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