Package org.apache.drill.exec.store.mongo

Class MongoRecordReader

java.lang.Object

org.apache.drill.exec.store.AbstractRecordReader

org.apache.drill.exec.store.mongo.MongoRecordReader

All Implemented Interfaces:

AutoCloseable, RecordReader

public class MongoRecordReader
extends AbstractRecordReader

Field Summary

Fields inherited from class org.apache.drill.exec.store.AbstractRecordReader

DEFAULT_TEXT_COLS_TO_READ

Fields inherited from interface org.apache.drill.exec.store.RecordReader

ALLOCATOR_INITIAL_RESERVATION, ALLOCATOR_MAX_RESERVATION

Constructor Summary

Constructors

Constructor	Description
MongoRecordReader(BaseMongoSubScanSpec subScanSpec, List<SchemaPath> projectedColumns, FragmentContext context, MongoStoragePlugin plugin)

Method Summary

Modifier and Type	Method	Description
void	close()
int	next()	Increments this record reader forward, writing via the provided output mutator into the output batch.
void	setup(OperatorContext context, OutputMutator output)	Configure the RecordReader with the provided schema and the record batch that should be written to.
String	toString()
protected Collection<SchemaPath>	transformColumns(Collection<SchemaPath> projectedColumns)

Methods inherited from class org.apache.drill.exec.store.AbstractRecordReader

allocate, getColumns, getDefaultColumnsToRead, hasNext, isSkipQuery, isStarQuery, setColumns

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Details

MongoRecordReader

public MongoRecordReader(BaseMongoSubScanSpec subScanSpec,
 List<SchemaPath> projectedColumns,
 FragmentContext context,
 MongoStoragePlugin plugin)

Method Details

transformColumns

protected Collection<SchemaPath> transformColumns(Collection<SchemaPath> projectedColumns)

Overrides:

transformColumns in class AbstractRecordReader

setup

public void setup(OperatorContext context,
 OutputMutator output)
           throws ExecutionSetupException

Description copied from interface: RecordReader

Configure the RecordReader with the provided schema and the record batch that should be written to.

Parameters:

context - operator context for the reader

output - The place where output for a particular scan should be written. The record reader is responsible for mutating the set of schema values for that particular record.

Throws:

ExecutionSetupException

next

public int next()

Description copied from interface: RecordReader

Increments this record reader forward, writing via the provided output mutator into the output batch.

Returns:

The number of additional records added to the output.

close

public void close()

toString

public String toString()

Overrides:

toString in class AbstractRecordReader