Package org.apache.drill.exec.store.pojo

Class PojoRecordReader<T>

java.lang.Object

org.apache.drill.exec.store.AbstractRecordReader

org.apache.drill.exec.store.pojo.AbstractPojoRecordReader<T>

org.apache.drill.exec.store.pojo.PojoRecordReader<T>

Type Parameters:

T - pojo class type

All Implemented Interfaces:

AutoCloseable, Iterable<T>, RecordReader

public class PojoRecordReader<T>
extends AbstractPojoRecordReader<T>

Reads values from the given list of pojo instances. Fields writers are determined based on pojo field class types.

Field Summary

Fields inherited from class org.apache.drill.exec.store.pojo.AbstractPojoRecordReader

DEFAULT_RECORDS_PER_BATCH, records, writers

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
PojoRecordReader(Class<T> pojoClass, List<T> records)
PojoRecordReader(Class<T> pojoClass, List<T> records, int maxRecordToRead)

Method Summary

Modifier and Type	Method	Description
protected Object	getFieldValue(T row, int fieldPosition)	Retrieves field value to be written based for given row and field position.
protected List<PojoWriter>	setupWriters(OutputMutator output)	Creates writers based on pojo field class types.
String	toString()

Methods inherited from class org.apache.drill.exec.store.pojo.AbstractPojoRecordReader

allocate, close, initWriter, iterator, next, setup

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

getColumns, getDefaultColumnsToRead, hasNext, isSkipQuery, isStarQuery, setColumns, transformColumns

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Details

PojoRecordReader

public PojoRecordReader(Class<T> pojoClass,
 List<T> records)

PojoRecordReader

public PojoRecordReader(Class<T> pojoClass,
 List<T> records,
 int maxRecordToRead)

Method Details

setupWriters

protected List<PojoWriter> setupWriters(OutputMutator output)
                                 throws ExecutionSetupException

Creates writers based on pojo field class types. Ignores static fields.

Specified by:

setupWriters in class AbstractPojoRecordReader<T>

Parameters:

output - output mutator

Returns:

list of pojo writers

Throws:

ExecutionSetupException

getFieldValue

protected Object getFieldValue(T row,
 int fieldPosition)

Description copied from class: AbstractPojoRecordReader

Retrieves field value to be written based for given row and field position.

Specified by:

getFieldValue in class AbstractPojoRecordReader<T>

Parameters:

row - current row

fieldPosition - current field position

Returns:

field value to be written for given row

toString

public String toString()

Overrides:

toString in class AbstractRecordReader