getOrInitialize
Retrieves or initializes an IdGenerator for the given NamedAggregate.
This method checks if an IdGenerator is already associated with the provided key. If not, it attempts to create one using the available factories. The first factory that successfully creates a non-null IdGenerator is used. If no factory can create an IdGenerator, an IllegalStateException is thrown.
Return
the IdGenerator associated with the key
Parameters
key
the NamedAggregate for which to retrieve or initialize the IdGenerator
Throws
if no AggregateIdGeneratorFactory can create an IdGenerator for the key