Using UUID with EclipseLink and PostgreSQL

Question

I want to use the PostgreSQL uuid type for objects' primary keys. For that I've created a converter (implementing the Converter interface). Bellow is the relevant code:

    @Override
    public void initialize(DatabaseMapping mapping, Session session) {
        final DatabaseField field;
        if (mapping instanceof DirectCollectionMapping) {
            field = ((DirectCollectionMapping) mapping).getDirectField();
        } else {
            field = mapping.getField();
        }

        field.setSqlType(Types.OTHER);
        field.setTypeName("uuid");
        field.setColumnDefinition("UUID");
    }

Then I've annotated the relevant entity X with the bellow annotations:

@Converter(name="uuidConverter",converterCalss=UUIDConverter.class)
@Convert("uuidConverter")
@Id
public UUID getId()
{
    return id;
}

The problem is that I have another class (Y) which has the following definition:

@ManyToOne(targetEntity = X.class)
@JoinColumn(name = "x_id")
public X getX();

Although EclipseLink created the tables as expected it sends a string to the database when trying to insert objects of type Y. Postgres returns the following error message:

column "id" is of type uuid but expression is of type character varying at character

Any solutions / work around will be appreciated.

Answer 1

I had some issues with EclipseLink JPA 2.1 + Postgresql + UUID as primary key but I find out different solution. I adopted AttributeConverter but I faced a problem with EclipseLink implementation that I resolved with this code:

@javax.persistence.Converter(autoApply = true)
public class PostgresUuidConverter implements AttributeConverter<UUID, Object> {        

    @Override
    public Object convertToDatabaseColumn(UUID uuid) {
        PostgresUuid object = new PostgresUuid();
        object.setType("uuid");
        try {
            if (uuid == null) {
                object.setValue(null);
            } else {
                object.setValue(uuid.toString());
            }
        } catch (SQLException e) {
            throw new IllegalArgumentException("Error when creating Postgres uuid", e);
        }
        return object;
    }

    @Override
    public UUID convertToEntityAttribute(Object dbData) {
        if (dbData instanceof String) {
            return UUID.fromString(dbData.toString());
        } else {    
            return (UUID) dbData;
        }
    }

}


public class PostgresUuid extends PGobject implements Comparable<Object> {

    private static final long serialVersionUID = 1L;

    @Override
    public int compareTo(Object arg0) {
        return 0;
    }

}

As I exaplined in detail in this post http://blog-ungarida.rhcloud.com/persisting-uuid-in-postgresql-using-jpa-eclipselink/