DATE Columns having NULL values --> NPE

[manticore-projects]

Exporting works in general, but not when there is a DATE column with NULL values.
VARCHAR null seems to work though.

Sample:

CREATE TABLE ifrsbox.cfe.instrument (
    id_instrument                    CHARACTER VARYING (40)  NOT NULL
    , id_instrument_commitment       CHARACTER VARYING (40)  NULL
    , id_instrument_type             CHARACTER VARYING (12)  NOT NULL
    , start_date                     TIMESTAMP               NOT NULL
    , end_date                       TIMESTAMP               NULL
    , id_currency                    CHARACTER VARYING (3)   NOT NULL
    , id_calendar                    CHARACTER VARYING (12)  NULL
    , id_business_day_convention     CHARACTER VARYING (12)  NULL
    , discount_curve                 CHARACTER VARYING (12)  NULL
    , discount_spread                CHARACTER VARYING (12)  NULL
)
;

INSERT INTO cfe.instrument
VALUES (    'deposit_1', NULL, 'deposit'
            , {d '2015-12-31'}, {d '2017-12-31'}, 'USD'
            , 'DEFAULT', 'P', NULL
            , NULL )
;

INSERT INTO cfe.instrument
VALUES (    'acc_1', NULL, 'curr_acc'
            , {d '2015-12-31'}, NULL, 'USD'
            , 'DEFAULT', NULL, NULL
            , NULL )
;

[manticore-projects]

Since I could not get it working or any feedback, I wrote my own based on latest Hadoop/Parquet:
https://manticore-projects.com/JDBCParquetWriter/index.html
https://github.com/manticore-projects/JDBCParquetWriter

Its a first working version, but it seems to get the Type/Column translation right.