private <S> DynamoDBTypeConverter<S,T> getConverter(Class<S> sourceType, ConvertibleType<T> type) {
            return scalars.getConverter(sourceType, type.targetType());
        }
Gets the scalar converter for the given source and target types.
aws-java-sdk-dynamodb/src/main/java/com/amazonaws/services/dynamodbv2/datamodeling/StandardModelFactories.java