org.apache.hadoop.hbase.filter
Class FirstKeyOnlyFilter
java.lang.Object
org.apache.hadoop.hbase.filter.FilterBase
org.apache.hadoop.hbase.filter.FirstKeyOnlyFilter
- All Implemented Interfaces:
- Filter, org.apache.hadoop.io.Writable
public class FirstKeyOnlyFilter
- extends FilterBase
A filter that will only return the first KV from each row.
This filter can be used to more efficiently perform row count operations.
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
FirstKeyOnlyFilter
public FirstKeyOnlyFilter()
reset
public void reset()
- Description copied from class:
FilterBase
- Filters that are purely stateless and do nothing in their reset() methods can inherit
this null/empty implementation.
- Specified by:
reset
in interface Filter
- Overrides:
reset
in class FilterBase
filterKeyValue
public Filter.ReturnCode filterKeyValue(KeyValue v)
- Description copied from class:
FilterBase
- Filters that dont filter by key value can inherit this implementation that
includes all KeyValues.
- Specified by:
filterKeyValue
in interface Filter
- Overrides:
filterKeyValue
in class FilterBase
- Parameters:
v
- the KeyValue in question
- Returns:
- code as described below
- See Also:
Filter.ReturnCode
write
public void write(DataOutput out)
throws IOException
- Throws:
IOException
readFields
public void readFields(DataInput in)
throws IOException
- Throws:
IOException
Copyright © 2011 The Apache Software Foundation. All Rights Reserved.