VectorCursor (druid-processing 28.0.0 API)

All Superinterfaces:

AutoCloseable, Closeable, VectorSizeInspector

All Known Implementing Classes:

FrameVectorCursor
```
public interface VectorCursor
extends VectorSizeInspector, Closeable
```
Vectorized cursor used during query execution. VectorCursors are returned by CursorFactory.makeVectorCursor(org.apache.druid.query.filter.Filter, org.joda.time.Interval, org.apache.druid.segment.VirtualColumns, boolean, int, org.apache.druid.query.QueryMetrics<?>) and are created by QueryableIndexCursorSequenceBuilder.buildVectorized(int). Unlike the non-vectorized version, VectorCursor does not have a getTime() method. This is because we are trying to avoid creating needlessly-small vectors when the time granularity is very fine. See VectorCursorGranularizer for a helper that makes it easier for query engines to do their own time granularization. An example of how to use the methods in this class:
```
   try (VectorCursor cursor = adapter.makeVectorCursor(...)) {
     // ProcessorClass is some vectorized processor class.
     ProcessorClass o = makeProcessor(cursor.getColumnSelectorFactory());
     for (; !cursor.isDone(); cursor.advance()) {
       o.process();
     }
   }
 
```

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`void`	`advance()`	Advances the cursor, skipping forward a number of rows equal to the current vector size.
`void`	`close()`	Close the cursor and release its resources.
`VectorColumnSelectorFactory`	`getColumnSelectorFactory()`	Returns a vectorized column selector factory.
`boolean`	`isDone()`	Returns false if the cursor is readable, true if it has nothing left to read.
`void`	`reset()`	Resets the cursor back to its original state.

Methods inherited from interface org.apache.druid.segment.vector.VectorSizeInspector
getCurrentVectorSize, getMaxVectorSize

- Method Detail
  - getColumnSelectorFactory
```
VectorColumnSelectorFactory getColumnSelectorFactory()
```
    Returns a vectorized column selector factory.
  - advance
```
void advance()
```
    Advances the cursor, skipping forward a number of rows equal to the current vector size.
  - isDone
```
boolean isDone()
```
    Returns false if the cursor is readable, true if it has nothing left to read.
  - reset
```
void reset()
```
    Resets the cursor back to its original state. Useful for query engines that want to make multiple passes.
  - close
```
void close()
```
    Close the cursor and release its resources.
    
    Specified by:
    
    close in interface AutoCloseable
    
    Specified by:
    
    close in interface Closeable