org.apache.hadoop.hbase.regionserver
Class ExplicitColumnTracker

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

public class ExplicitColumnTracker
extends Object
implements ColumnTracker

This class is used for the tracking and enforcement of columns and numbers of versions during the course of a Get or Scan operation, when explicit column qualifiers have been asked for in the query. With a little magic (see ScanQueryMatcher), we can use this matcher for both scans and gets. The main difference is 'next' and 'done' collapse for the scan case (since we see all columns in order), and we only reset between rows.

This class is utilized by ScanQueryMatcher through two methods: