For Spring Boot working with Spring Data for a uni-directional @OneToMany relation, such as Parent and Child, their codes are respectively as follows:

@Entity
@Table(name="parent")
public class Parent implements Serializable {

    ...

    @OneToMany(fetch=FetchType.LAZY, cascade=CascadeType.REMOVE, orphanRemoval=true)
    @JoinColumn(name="parent_id")
    @OrderBy("id")
    private final Set<Child> children = new LinkedHashSet<>();

    ...

}

and

@Entity
@Table(name="child")
public class Child implements Serializable {

    ...

}

And having a custom ParentRepository interface extending CrudRepository<T,ID>, it has defined explicitly a custom method named findByIdWithChildren working with @Query and using JOIN FETCH

Therefore using Spring MVC - through HTML (Thymeleaf) - through @GetMapping is possible:

Group I

• (A) Find and show only a specific Parent - through the default findById method. (Ok)
• (B) Find and show a specific Parent with all its Child - through the custom findByIdWithChildren method. (Ok)
• (C) Find and show only all the Parent - through the default findAll method. (Ok)

Therefore until here all is Ok. The problem is when REST is used, exists now the following behavior as follows.

Group II

• (A) behaves as (B) Group I (Not desired)
• (B) behaves as (B) Group I (Ok)
• (C) Find and show all the Parent but with all their Child (Not desired)

Using @JsonBackReference as follows

    @JsonBackReference
    @OneToMany(fetch=FetchType.LAZY, cascade=CascadeType.REMOVE, orphanRemoval=true)
    @JoinColumn(name="parent_id")
    @OrderBy("id")
    private final Set<Child> children = new LinkedHashSet<>();

happens as follows:

Group III

• (A) Find and show only a specific Parent - through the default findById method. (OK)
• (B) Find and show a specific Parent but without all its Child - through the custom findByIdWithChildren method. (Not desired)
• (C) Find and show only all the Parent - through the default findAll method. (OK)

Question

• How to reach the same kind of output for Rest as HTML?

Show only a specific parent (without its children), show a specific parent with its children, show only all the parents (without their children)