org.apache.hadoop.hbase.regionserver
Class ScanWildcardColumnTracker

java.lang.Object
  extended by org.apache.hadoop.hbase.regionserver.ScanWildcardColumnTracker
All Implemented Interfaces:
ColumnTracker

public class ScanWildcardColumnTracker
extends Object
implements ColumnTracker

Keeps track of the columns for a scan if they are not explicitly specified


Constructor Summary
ScanWildcardColumnTracker(int maxVersion)
          Return maxVersions of every row.
 
Method Summary
 ScanQueryMatcher.MatchCode checkColumn(byte[] bytes, int offset, int length, long timestamp)
          Can only return INCLUDE or SKIP, since returning "NEXT" or "DONE" would imply we have finished with this row, when this class can't figure that out.
 boolean done()
          We can never know a-priori if we are done, so always return false.
 ColumnCount getColumnHint()
          Used by matcher and scan/get to get a hint of the next column to seek to after checkColumn() returns SKIP.
 void reset()
          Resets the Matcher
 void update()
          Updates internal variables in between files
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

ScanWildcardColumnTracker

public ScanWildcardColumnTracker(int maxVersion)
Return maxVersions of every row.

Parameters:
maxVersion -
Method Detail

checkColumn

public ScanQueryMatcher.MatchCode checkColumn(byte[] bytes,
                                              int offset,
                                              int length,
                                              long timestamp)
Can only return INCLUDE or SKIP, since returning "NEXT" or "DONE" would imply we have finished with this row, when this class can't figure that out.

Specified by:
checkColumn in interface ColumnTracker
Parameters:
bytes -
offset -
length -
timestamp -
Returns:
The match code instance.

update

public void update()
Description copied from interface: ColumnTracker
Updates internal variables in between files

Specified by:
update in interface ColumnTracker

reset

public void reset()
Description copied from interface: ColumnTracker
Resets the Matcher

Specified by:
reset in interface ColumnTracker

getColumnHint

public ColumnCount getColumnHint()
Used by matcher and scan/get to get a hint of the next column to seek to after checkColumn() returns SKIP. Returns the next interesting column we want, or NULL there is none (wildcard scanner).

Specified by:
getColumnHint in interface ColumnTracker
Returns:
The column count.

done

public boolean done()
We can never know a-priori if we are done, so always return false.

Specified by:
done in interface ColumnTracker
Returns:
false


Copyright © 2011 The Apache Software Foundation. All Rights Reserved.