Two id in table Hibernate

Question

Is it possible for two fields to be id in a Hibernate table? I have two ids that need to be single in even table. But I don’t know how to implement.

Answer 1

Can do using @Embeddedid

You can do it like this:

@Embeddable
class ClassePrimeira implements Serializable {

@Id
Integer chaveUm;
@Id
Integer chaveDois;

// get’s e set’s  

}

@Entity
public class Classe {

@EmbeddedId
private ClassePrimeira id;
// get’s e set’s  
}

Annotation @Id, @Idclass, or @Embeddedid for Composite Keys: When a primary key consists of multiple columns, we need a different strategy to group them so that we can allow that the persistence tool manipulates key values as a single object. That way, we need to create a class that represents this primary key. This class as a general rule must be public, must have a default constructor, must be serializable, and must implement the hashcode() and equals() methods that allow Hibernate test collisions on primary keys.

Source: https://www.devmedia.com.br/mapeamento-no-hibernate-com-anotacoes/29472

While the above shows you the basics of how to declare two id’s in the same template, you can get into the Hibernate documentation: http://docs.jboss.org/hibernate/orm4.3/manual/en-US/html_single/#Mapping-declaration-id, and although it is in English in item 5.1.2.1 there is a good explanation for what you want to do.