[nosql-dev] @Convert annotation for the Entities (Document)

[Dmitry Repchevsky <redmitry@xxxxxxx>]

Hello,

Implementing the polymorphism via AttributeConverter interface, I found 
that it supposed for the primitive types.
I still can make it works, but IMHO the behavior should be changed. Here 
is the problem:

https://github.com/eclipse/jnosql/blob/d68add32d7a09e601c4ef3aef666c14cd885c13e/mapping/mapping-document/src/main/java/org/eclipse/jnosql/mapping/document/DocumentFieldConverters.java#L130

if (Objects.nonNull(document)) {
    Value value = document.getValue();
    Optional<Class<? extends AttributeConverter<X, Y>>> 
optionalConverter = field.getConverter();
    if (optionalConverter.isPresent()) {
        AttributeConverter<X, Y> attributeConverter = 
converter.getConverters().get(optionalConverter.get());
        Object attributeConverted = 
attributeConverter.convertToEntityAttribute((Y) value.get());
        field.write(instance, 
field.getValue(Value.of(attributeConverted)));
    } else {
        field.write(instance, field.getValue(value));
    }
}

The code supposes that for the @Converter the document that describes 
the value is a primitive (value.get())

This obliges to define the converter as:

@Convert(MeasurementValueCoverter.class)
private MeasurementValueEntity measurementValue;
...
public class MeasurementValueCoverter implements 
AttributeConverter<MeasurementValueEntity, List<Document>> {

Note, that List<Document> in this case is not the document itself, but 
its properties!
IMHO, for the Entities converter should receive the Document, so we can 
parse it correctly.

Cheers,

Dmitry