there is only one record querybasedhiveconversionentity to be read . this querybasedhiveconversionentity isremoved from #conversionentities list after it is read . so when gobblin runtime calls this method the second time , it returns a null concode_field_sep List<QueryBasedHiveConversionEntity> conversionEntities concode_field_sep long getHighWatermark concode_elem_sep long getExpectedRecordCount concode_elem_sep void close concode_elem_sep Schema getSchema
QueryBasedHiveConversionEntity function ( QueryBasedHiveConversionEntity arg0 ) { if ( this . conversionEntities . isEmpty ( ) ) { return null ; } return this . conversionEntities . remove ( 0 ) ; }