Básicamente estás buscando extractYear()
que se asigna al $year
operador con MongoDB:
Aggregation aggregation = Aggregation.newAggregation(
Aggregation.match(new Criteria().andOperator(criteria())),
Aggregation.project().and("invoiceDate").extractYear().as("_id"),
Aggregation.group("_id"),
Aggregation.sort(Sort.Direction.DESC, "_id)
)
Por lo general, esto debe ingresar en un $project
para hacer felices a los ayudantes.
Si realmente desea la expresión dentro del $group
luego puede agregar una expresión de operación personalizada:
Aggregation aggregation = Aggregation.newAggregation(
Aggregation.match(new Criteria().andOperator(criteria())),
new AggregationOperation() {
@Override
public Document toDocument(AggregationOperationContext aggregationOperationContext) {
return new Document("$group",
new Document("_id", new Document("$year","$invoiceDate") )
);
}
},
Aggregation.sort(Sort.Direction.DESC, "_id)
)