Package org.apache.hadoop.hbase.coprocessor.example

Class DelegatingInternalScanner

java.lang.Object

org.apache.hadoop.hbase.coprocessor.example.DelegatingInternalScanner

All Implemented Interfaces:

Closeable, AutoCloseable, InternalScanner

@Private
public class DelegatingInternalScanner
extends Object
implements InternalScanner

A simple delegation for doing filtering on InternalScanner.

Field Summary

Fields

Modifier and Type	Field	Description
protected final InternalScanner	scanner

Constructor Summary

Constructors

Constructor	Description
DelegatingInternalScanner(InternalScanner scanner)

Method Summary

Modifier and Type	Method	Description
void	close()	Closes the scanner and releases any resources it has allocated
boolean	next(List<? super ExtendedCell> result, ScannerContext scannerContext)	Grab the next row's worth of values.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.hadoop.hbase.regionserver.InternalScanner

next

Field Details

scanner

protected final InternalScanner scanner

Constructor Details

DelegatingInternalScanner

public DelegatingInternalScanner(InternalScanner scanner)

Method Details

next

public boolean next(List<? super ExtendedCell> result,
 ScannerContext scannerContext)
             throws IOException

Description copied from interface: InternalScanner

Grab the next row's worth of values.

The generic type for the output list result means we will only add ExtendedCell to it. This is useful for the code in HBase as we can pass List<ExtendedCell> here to avoid casting, but may cause some troubles for coprocessors which implement this method. In general, all cells created via the CellBuilder are actually ExtendedCells, so if you want to add something to the result list, you can just cast it to ExtendedCell, although it is marked as IA.Private.

Specified by:

next in interface InternalScanner

Parameters:

result - return output array. We will only add ExtendedCell to this list, but for CP users, you'd better just use RawCell as ExtendedCell is IA.Private.

Returns:

true if more rows exist after this one, false if scanner is done

Throws:

IOException

close

public void close()
           throws IOException

Description copied from interface: InternalScanner

Closes the scanner and releases any resources it has allocated

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Specified by:

close in interface InternalScanner

Throws:

IOException