ReaderColumns (trino-hive 360 API)

java.lang.Object
- io.trino.plugin.hive.ReaderColumns

```
public class ReaderColumns
extends Object
```
Stores a mapping between - the projected columns required by a connector level pagesource and - the columns supplied by format-specific page source
Currently used in HivePageSource.

Constructor Summary

Constructors
Constructor Description

ReaderColumns(List<? extends ColumnHandle> readerColumns, List<Integer> readerBlockIndices)

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`List<ColumnHandle>`	`get()`	returns the actual list of columns being read by underlying page source or record cursor in order.
`ColumnHandle`	`getForColumnAt(int index)`	For a column required by the wrapper page source, returns the column read by the delegate page source or record cursor.
`int`	`getPositionForColumnAt(int index)`	For a channel expected by wrapper page source, returns the channel index in the underlying page source or record cursor.

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

- Constructor Detail
  - ReaderColumns
```
public ReaderColumns(List<? extends ColumnHandle> readerColumns,
                     List<Integer> readerBlockIndices)
```
- Method Detail
  - getForColumnAt
```
public ColumnHandle getForColumnAt(int index)
```
    For a column required by the wrapper page source, returns the column read by the delegate page source or record cursor.
  - getPositionForColumnAt
```
public int getPositionForColumnAt(int index)
```
    For a channel expected by wrapper page source, returns the channel index in the underlying page source or record cursor.
  - get
```
public List<ColumnHandle> get()
```
    returns the actual list of columns being read by underlying page source or record cursor in order.