Package org.apache.cassandra.index.sai.disk.v1

Class ColumnCompletionMarkerUtil

java.lang.Object

org.apache.cassandra.index.sai.disk.v1.ColumnCompletionMarkerUtil

public class ColumnCompletionMarkerUtil
extends Object

Utility class for creating and reading the column completion marker, IndexComponent.COLUMN_COMPLETION_MARKER.

The file has a header and a footer, as written by SAICodecUtils.writeHeader(IndexOutput) and SAICodecUtils.writeFooter(IndexOutput). The only content of the file is a single byte indicating whether the column index is empty or not. If the index is empty the completion marker will be the only per-index component.

Constructor Summary

Constructors

Constructor	Description
ColumnCompletionMarkerUtil()

Method Summary

Modifier and Type	Method	Description
static void	create(IndexDescriptor descriptor, IndexIdentifier indexIdentifier, boolean isEmpty)	Creates a column index completion marker for the specified column index, storing in it whether the index is empty.
static boolean	isEmptyIndex(IndexDescriptor descriptor, IndexIdentifier indexIdentifier)	Reads the column index completion marker and returns whether if the index is empty.

Methods inherited from class java.lang.Object

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

Constructor Details

ColumnCompletionMarkerUtil

public ColumnCompletionMarkerUtil()

Method Details

create

public static void create(IndexDescriptor descriptor,
 IndexIdentifier indexIdentifier,
 boolean isEmpty)
                   throws IOException

Creates a column index completion marker for the specified column index, storing in it whether the index is empty.

Parameters:

descriptor - the index descriptor

indexIdentifier - the column index identifier

isEmpty - whether the index is empty

Throws:

IOException

isEmptyIndex

public static boolean isEmptyIndex(IndexDescriptor descriptor,
 IndexIdentifier indexIdentifier)
                            throws IOException

Reads the column index completion marker and returns whether if the index is empty.

Parameters:

descriptor - the index descriptor

indexIdentifier - the column index identifier

Returns:

true if the index is empty, false otherwise.

Throws:

IOException