Question

i would use a ModelBase with an ID and a Timestamp for every class/entity. But when i user the Long type for the Primary Key in the JPARepository<> interface i get the message

Not an entity: class java.lang.Long

Code:

@MappedSuperclass
public class ModelBase implements Serializable {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;

    @Column(nullable = false, columnDefinition = "datetime")
    private Date lastModified;

    public Long getId() {
        return id;
    }

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

    public Date getLastModified() {
        return lastModified;
    }

    public void setLastModified(Date lastModified) {
        this.lastModified = lastModified;
    }

    @PreUpdate
    @PrePersist
    public void updateLastModified() {
        lastModified = new Date();
    }

}

Modelclass inheritanced from Modelbase

@Entity
@Table(name = "Name")
public class Name extends ModelBase implements Serializable {}

Repo

public interface NameRepository extends JpaRepository<Long, Name>{}

what am i doing wrong?

thanks

Answer 1

It’s backwards:

JpaRepository<Name, Long>

First the entity, then the ID. Check JPARepository javadoc.