Basic' attribute type should not be 'Persistence Entity'

Question

I am using Spring Boot for creating my REST API. I have a "Component" class, which is as follows:

@Entity
public class Component {
   @Id @GeneratedValue
   private Long id;
   private String name;
   private String unit;
   private double quantity;

   public Component(){

   }


   public Component(Long id, String name, String unit, double quantity){
       this.id = id;
       this.name = name;
       this.unit = unit;
       this.quantity = quantity;
   }

  //getters
  //setters

I have a product class which consists of "Component"s:

@Entity
public class Product{
    @Id @GeneratedValue
    private Long id;
    private String name;
    private Component productComponent;

}

Here is the Error that I am getting: It is highlighting the "private Component productComponent" line in the Product class, and saying the following:

Basic' attribute type should not be 'Persistence Entity'

What is the reason behind such error?

Answer 1

I fixed the above problem by adding @ManyToOne and @JoinColumn:

@Entity
public class Product{
    @Id @GeneratedValue
    private Long id;
    private String name;
    @ManyToOne
    @JoinColumn
    private Component productComponent;
}