Doubts how to leave a unique attribute - JPA

Question

I am creating an entity, and I have a CPF field and this field that is unique, how to map this CPF field?

My entity.

@Entity

public class Client {

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long codigo;
private String nome;
private String cpf;
private String telefoneFixo;
private String telefoneCelular;

Answer 1

You can do the class level inside the annotation @Table, follows an example:

@Entity
@Table(uniqueConstraints={@UniqueConstraint(columnNames={"cpf"})})
public class Entidade{

    @Column
    public String cpf;
}

Source: http://docs.oracle.com/javaee/7/api/javax/persistence/UniqueConstraint.html

Answer 2

Try:

@Column(unique=true)
private String cpf;

EDIT

The suggestion sent by adelmo00 is a better practice than the one I suggested because it allows the definition of one or more fields as unique. If you are sure that only the Cpf field needs to be unique there is no problem in using my suggestion, however, if you later want to define more attributes as unique, not to be typing @Column(Unique=true) for each field, I recommend using adelmo00’s suggestion.