Question

I’d like to add some additional methods to a Seam entity. These methods don’t have a own column in the database. They just format and combinate some columns.

@Entity
@Table(name = "event", schema = "public")
public class Event implements java.io.Serializable {

    // [...]

    @Column(name = "status", nullable = false, length = 13)
    @NotNull
    @Length(max = 13)
    private String status;

    public String getStatus() {
        return this.status;
    }

    public void setStatus(String status) {
        this.status = status;
    }

    public String getSpecialStatus() { // not allowed as there is no setter and no column 'specialStatus'
        return someValue;
    }

    // [...]
}

This code throws the following exception:

javax.persistence.PersistenceException: org.hibernate.PropertyNotFoundException: Could not find a setter for property specialStatus in class foobar.entity.Event

I tried to add the following setter:

private void setSpecialStatus(String status){
    throw new NotImplementedException();
}

The exception changes to:

javax.persistence.PersistenceException: org.hibernate.HibernateException: Missing column: specialStatus in public.event

Does anyone know if there is a way to solve this problem? Or is it bad practice to add additional methods to an entity? (If so, how should I implement it?)

Answer 1

I’m not sure how this will interact with your use of annotations on fields, but if you annotate your getters, you could use the @Transient annotation to tell Hibernate this is not to be persisted.

@Transient
public String getSpecialStatus() { 
    return someValue;
}