org.apache.hadoop.hbase.client

Class ClientUtil

java.lang.Object

org.apache.hadoop.hbase.client.ClientUtil

@InterfaceAudience.Private
public class ClientUtil
extends Object

Constructor Summary

Constructors

Constructor and Description
ClientUtil()

Method Summary

Modifier and Type	Method and Description
static boolean	areScanStartRowAndStopRowEqual(byte[] startRow, byte[] stopRow)
static byte[]	calculateTheClosestNextRowKeyForPrefix(byte[] rowKeyPrefix) When scanning for a prefix the scan should stop immediately after the the last row that has the specified prefix.
static Cursor	createCursor(byte[] row)

Methods inherited from class java.lang.Object

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

Constructor Detail

ClientUtil

public ClientUtil()

Method Detail

areScanStartRowAndStopRowEqual

public static boolean areScanStartRowAndStopRowEqual(byte[] startRow,
                                                     byte[] stopRow)

createCursor

public static Cursor createCursor(byte[] row)

calculateTheClosestNextRowKeyForPrefix

public static byte[] calculateTheClosestNextRowKeyForPrefix(byte[] rowKeyPrefix)

When scanning for a prefix the scan should stop immediately after the the last row that has the specified prefix. This method calculates the closest next rowKey immediately following the given rowKeyPrefix.

IMPORTANT: This converts a rowKeyPrefix into a rowKey.

If the prefix is an 'ASCII' string put into a byte[] then this is easy because you can simply increment the last byte of the array. But if your application uses real binary rowids you may run into the scenario that your prefix is something like:

{ 0x12, 0x23, 0xFF, 0xFF }
Then this stopRow needs to be fed into the actual scan
{ 0x12, 0x24 } (Notice that it is shorter now)
This method calculates the correct stop row value for this usecase.

Parameters:

rowKeyPrefix - the rowKeyPrefix.

Returns:

the closest next rowKey immediately following the given rowKeyPrefix.