@Entity annotation defines that a class can be mapped to a table. And that is it, it is just a marker, like for example Serializable interface. And why @Entity annotation is mandatory? … well, it is the way how JPA is designed. When you create a new entity you have to do at least two … Read more
You are missing a field annotated with @Id. Each @Entity needs an @Id – this is the primary key in the database. If you don’t want your entity to be persisted in a separate table, but rather be a part of other entities, you can use @Embeddable instead of @Entity. If you want simply a … Read more
Your annotations look fine. Here are the things to check: make sure the annotation is javax.persistence.Entity, and not org.hibernate.annotations.Entity. The former makes the entity detectable. The latter is just an addition. if you are manually listing your entities (in persistence.xml, in hibernate.cfg.xml, or when configuring your session factory), then make sure you have also listed the ScopeTopic entity make … Read more