RecordIterator (exec/Java Execution Engine 1.12.0 API)

java.lang.Object
- org.apache.drill.exec.record.RecordIterator

All Implemented Interfaces:

Iterable<VectorWrapper<?>>, VectorAccessible
```
public class RecordIterator
extends Object
implements VectorAccessible
```
RecordIterator iterates over incoming record batches one record at a time. It allows to mark a position during iteration and reset back. RecordIterator will hold onto multiple record batches in order to support resetting beyond record batch boundary.

Constructor Summary

Constructors
Constructor and Description
`RecordIterator(RecordBatch incoming, AbstractRecordBatch<?> outgoing, OperatorContext oContext, int inputIndex)`
`RecordIterator(RecordBatch incoming, AbstractRecordBatch<?> outgoing, OperatorContext oContext, int inputIndex, boolean enableMarkAndReset)`

Method Summary

Methods
Modifier and Type	Method and Description
`Map<com.google.common.collect.Range<Long>,RecordBatchData>`	`cachedBatches()`
`void`	`clear()`
`void`	`clearInflightBatches()`
`void`	`close()`
`boolean`	`finished()`
`void`	`forward(long delta)`
`int`	`getCurrentPosition()`
`int`	`getInnerRecordCount()`
`RecordBatch.IterOutcome`	`getLastOutcome()`
`long`	`getOuterPosition()`
`int`	`getRecordCount()` Get the number of records.
`BatchSchema`	`getSchema()` Get the schema of the current RecordBatch.
`SelectionVector2`	`getSelectionVector2()`
`SelectionVector4`	`getSelectionVector4()`
`long`	`getTotalRecordCount()`
`VectorWrapper<?>`	`getValueAccessorById(Class<?> clazz, int... ids)`
`TypedFieldId`	`getValueVectorId(SchemaPath path)` Get the value vector type and id for the given schema path.
`Iterator<VectorWrapper<?>>`	`iterator()`
`void`	`mark()`
`RecordBatch.IterOutcome`	`next()` Move iterator to next record.
`void`	`prepare()` buildSchema calls next() in order to read schema quikcly.
`void`	`reset()`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - RecordIterator
```
public RecordIterator(RecordBatch incoming,
              AbstractRecordBatch<?> outgoing,
              OperatorContext oContext,
              int inputIndex)
```
  - RecordIterator
```
public RecordIterator(RecordBatch incoming,
              AbstractRecordBatch<?> outgoing,
              OperatorContext oContext,
              int inputIndex,
              boolean enableMarkAndReset)
```
- Method Detail
  - mark
```
public void mark()
```
  - reset
```
public void reset()
```
  - forward
```
public void forward(long delta)
```
  - prepare
```
public void prepare()
```
    buildSchema calls next() in order to read schema quikcly. Make sure we have fetched next non-empty batch at the end of the prepare. After prepare position of iterator is at 0.
  - next
```
public RecordBatch.IterOutcome next()
```
    Move iterator to next record.
    
    Returns:
    Status of current record batch read.
  - finished
```
public boolean finished()
```
  - getLastOutcome
```
public RecordBatch.IterOutcome getLastOutcome()
```
  - getTotalRecordCount
```
public long getTotalRecordCount()
```
  - getInnerRecordCount
```
public int getInnerRecordCount()
```
  - getOuterPosition
```
public long getOuterPosition()
```
  - getCurrentPosition
```
public int getCurrentPosition()
```
  - cachedBatches
```
public Map<com.google.common.collect.Range<Long>,RecordBatchData> cachedBatches()
```
  - getValueAccessorById
```
public VectorWrapper<?> getValueAccessorById(Class<?> clazz,
                                    int... ids)
```
    Specified by:
    
    getValueAccessorById in interface VectorAccessible
  - getValueVectorId
```
public TypedFieldId getValueVectorId(SchemaPath path)
```
    Description copied from interface: VectorAccessible
    
    Get the value vector type and id for the given schema path. The TypedFieldId should store a fieldId which is the same as the ordinal position of the field within the Iterator provided this classes implementation of Iterable.
    
    Specified by:
    
    getValueVectorId in interface VectorAccessible
    
    Parameters:
    path - the path where the vector should be located.
    
    Returns:
    the local field id associated with this vector. If no field matches this path, this will return a null TypedFieldId
  - getSchema
```
public BatchSchema getSchema()
```
    Description copied from interface: VectorAccessible
    
    Get the schema of the current RecordBatch. This changes if and only if a *_NEW_SCHEMA IterOutcome is provided.
    
    Specified by:
    
    getSchema in interface VectorAccessible
    
    Returns:
    schema of the current batch
  - getRecordCount
```
public int getRecordCount()
```
    Description copied from interface: VectorAccessible
    
    Get the number of records.
    
    Specified by:
    
    getRecordCount in interface VectorAccessible
    
    Returns:
    number of records
  - iterator
```
public Iterator<VectorWrapper<?>> iterator()
```
    Specified by:
    
    iterator in interface Iterable<VectorWrapper<?>>
  - getSelectionVector2
```
public SelectionVector2 getSelectionVector2()
```
    Specified by:
    
    getSelectionVector2 in interface VectorAccessible
  - getSelectionVector4
```
public SelectionVector4 getSelectionVector4()
```
    Specified by:
    
    getSelectionVector4 in interface VectorAccessible
  - clear
```
public void clear()
```
  - clearInflightBatches
```
public void clearInflightBatches()
```
  - close
```
public void close()
```

Class RecordIterator

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

RecordIterator

RecordIterator

Method Detail

mark

reset

forward

prepare

next

finished

getLastOutcome

getTotalRecordCount

getInnerRecordCount

getOuterPosition

getCurrentPosition

cachedBatches

getValueAccessorById

getValueVectorId

getSchema

getRecordCount

iterator

getSelectionVector2

getSelectionVector4

clear

clearInflightBatches

close