NULL cannot be inserted as a Parquet map (and as key in a map)

CREATE TABLE parquet_map_type_string (
id int,
stringMap map<string, string>
) stored as parquet;

insert into parquet_map_type_string SELECT 1, MAP('k1', null, 'k2', 'v2'); -- NULL as value, works
insert into parquet_map_type_string (id) VALUES (2); -- NULL as map, fails
insert into parquet_map_type_string SELECT 3, MAP(null, 'k3', 'k4', 'v4'); -- NULL as key, fails

Caused by: java.lang.NullPointerException
	at org.apache.parquet.io.api.Binary$FromStringBinary.encodeUTF8(Binary.java:218)
	at org.apache.parquet.io.api.Binary$FromStringBinary.<init>(Binary.java:209)
	at org.apache.parquet.io.api.Binary.fromString(Binary.java:537)
	at org.apache.hadoop.hive.ql.io.parquet.write.DataWritableWriter$StringDataWriter.write(DataWritableWriter.java:474)
	at org.apache.hadoop.hive.ql.io.parquet.write.DataWritableWriter$MapDataWriter.write(DataWritableWriter.java:354)
	at org.apache.hadoop.hive.ql.io.parquet.write.DataWritableWriter$GroupDataWriter.write(DataWritableWriter.java:228)
	at org.apache.hadoop.hive.ql.io.parquet.write.DataWritableWriter$MessageDataWriter.write(DataWritableWriter.java:251)
	at org.apache.hadoop.hive.ql.io.parquet.write.DataWritableWriter.write(DataWritableWriter.java:115)
	at org.apache.hadoop.hive.ql.io.parquet.write.DataWritableWriteSupport.write(DataWritableWriteSupport.java:76)
	at org.apache.hadoop.hive.ql.io.parquet.write.DataWritableWriteSupport.write(DataWritableWriteSupport.java:35)
	at org.apache.parquet.hadoop.InternalParquetRecordWriter.write(InternalParquetRecordWriter.java:128)
	at org.apache.parquet.hadoop.ParquetRecordWriter.write(ParquetRecordWriter.java:182)
	at org.apache.parquet.hadoop.ParquetRecordWriter.write(ParquetRecordWriter.java:44)
	at org.apache.hadoop.hive.ql.io.parquet.write.ParquetRecordWriterWrapper.write(ParquetRecordWriterWrapper.java:161)
	at org.apache.hadoop.hive.ql.io.parquet.write.ParquetRecordWriterWrapper.write(ParquetRecordWriterWrapper.java:174)
	at org.apache.hadoop.hive.ql.exec.FileSinkOperator.process(FileSinkOperator.java:1160)
	at org.apache.hadoop.hive.ql.exec.Operator.forward(Operator.java:888)
	at org.apache.hadoop.hive.ql.exec.SelectOperator.process(SelectOperator.java:94)
	at org.apache.hadoop.hive.ql.exec.Operator.forward(Operator.java:888)
	at org.apache.hadoop.hive.ql.exec.TableScanOperator.process(TableScanOperator.java:173)
	at org.apache.hadoop.hive.ql.exec.MapOperator$MapOpCtx.forward(MapOperator.java:155)
	at org.apache.hadoop.hive.ql.exec.MapOperator.process(MapOperator.java:550)