ReaderIndex (Drill : 1.20.3 API)

java.lang.Object
- org.apache.drill.exec.physical.resultSet.model.ReaderIndex

All Implemented Interfaces:

ColumnReaderIndex

Direct Known Subclasses:

DirectRowIndex, HyperRowIndex, IndirectRowIndex
```
public abstract class ReaderIndex
extends Object
implements ColumnReaderIndex
```
Row set index base class used when indexing rows within a row set for a row set reader. Keeps track of the current position, which starts before the first row, meaning that the client must call next() to advance to the first row.

Field Summary

Fields
Modifier and Type Field and Description

protected int position

protected Supplier<Integer> rowCount

Fields
Modifier and Type	Field and Description
`protected int`	`position`
`protected Supplier<Integer>`	`rowCount`

Constructor Summary

Constructors
Constructor and Description

ReaderIndex(Supplier<Integer> rowCount)

Constructors
Constructor and Description
`ReaderIndex(Supplier<Integer> rowCount)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`hasNext()` Reports if the index has another item.
`int`	`logicalIndex()` Ordinal index within the batch or array.
`boolean`	`next()` Advances the index to the next position.
`void`	`set(int index)`
`int`	`size()` Return the number of items that this index indexes: top-level record count for the root index; total element count for nested arrays.

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

Methods inherited from interface org.apache.drill.exec.vector.accessor.ColumnReaderIndex
hyperVectorIndex, offset

- Field Detail
  - position
```
protected int position
```
  - rowCount
```
protected final Supplier<Integer> rowCount
```
- Constructor Detail
  - ReaderIndex
```
public ReaderIndex(Supplier<Integer> rowCount)
```
- Method Detail
  - set
```
public void set(int index)
```
  - logicalIndex
```
public int logicalIndex()
```
    Description copied from interface: ColumnReaderIndex
    
    Ordinal index within the batch or array. Increments from -1. (The position before the first item.) Identifies the logical row number of top-level records, or the array element for arrays. Actual physical index may be different if an indirection layer is in use.
    
    Specified by:
    
    logicalIndex in interface ColumnReaderIndex
    
    Returns:
    
    logical read index
  - size
```
public int size()
```
    Description copied from interface: ColumnReaderIndex
    
    Return the number of items that this index indexes: top-level record count for the root index; total element count for nested arrays.
    
    Specified by:
    
    size in interface ColumnReaderIndex
    
    Returns:
    
    element count at this index level
  - next
```
public boolean next()
```
    Description copied from interface: ColumnReaderIndex
    Advances the index to the next position. Used:
    - At the top level for normal readers or
    Specified by:
    
    next in interface ColumnReaderIndex
    
    Returns:
    
    true if another value is available, false if EOF
  - hasNext
```
public boolean hasNext()
```
    Description copied from interface: ColumnReaderIndex
    
    Reports if the index has another item.
    
    Specified by:
    
    hasNext in interface ColumnReaderIndex
    
    Returns:
    
    if more rows remain. That is, if a call to ColumnReaderIndex.next() would return true.

Class ReaderIndex

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface org.apache.drill.exec.vector.accessor.ColumnReaderIndex

Field Detail

position

rowCount

Constructor Detail

ReaderIndex

Method Detail

set

logicalIndex

size

next

hasNext