org.apache.hadoop.mapred.lib.aggregate
Class ValueAggregatorBaseDescriptor

java.lang.Object
  extended by org.apache.hadoop.mapreduce.lib.aggregate.ValueAggregatorBaseDescriptor
      extended by org.apache.hadoop.mapred.lib.aggregate.ValueAggregatorBaseDescriptor
All Implemented Interfaces:
ValueAggregatorDescriptor

@InterfaceAudience.Public
@InterfaceStability.Stable
public class ValueAggregatorBaseDescriptor
extends ValueAggregatorBaseDescriptor
implements ValueAggregatorDescriptor

This class implements the common functionalities of the subclasses of ValueAggregatorDescriptor class.


Field Summary
static String DOUBLE_VALUE_SUM
           
static String LONG_VALUE_MAX
           
static String LONG_VALUE_MIN
           
static String LONG_VALUE_SUM
           
static String STRING_VALUE_MAX
           
static String STRING_VALUE_MIN
           
static String UNIQ_VALUE_COUNT
           
static String VALUE_HISTOGRAM
           
 
Fields inherited from class org.apache.hadoop.mapreduce.lib.aggregate.ValueAggregatorBaseDescriptor
inputFile
 
Fields inherited from interface org.apache.hadoop.mapred.lib.aggregate.ValueAggregatorDescriptor
ONE, TYPE_SEPARATOR
 
Constructor Summary
ValueAggregatorBaseDescriptor()
           
 
Method Summary
 void configure(JobConf job)
          get the input file name.
static Map.Entry<Text,Text> generateEntry(String type, String id, Text val)
           
static ValueAggregator generateValueAggregator(String type)
           
 
Methods inherited from class org.apache.hadoop.mapreduce.lib.aggregate.ValueAggregatorBaseDescriptor
configure, generateKeyValPairs, generateValueAggregator
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface org.apache.hadoop.mapreduce.lib.aggregate.ValueAggregatorDescriptor
configure, generateKeyValPairs
 

Field Detail

UNIQ_VALUE_COUNT

public static final String UNIQ_VALUE_COUNT
See Also:
Constant Field Values

LONG_VALUE_SUM

public static final String LONG_VALUE_SUM
See Also:
Constant Field Values

DOUBLE_VALUE_SUM

public static final String DOUBLE_VALUE_SUM
See Also:
Constant Field Values

VALUE_HISTOGRAM

public static final String VALUE_HISTOGRAM
See Also:
Constant Field Values

LONG_VALUE_MAX

public static final String LONG_VALUE_MAX
See Also:
Constant Field Values

LONG_VALUE_MIN

public static final String LONG_VALUE_MIN
See Also:
Constant Field Values

STRING_VALUE_MAX

public static final String STRING_VALUE_MAX
See Also:
Constant Field Values

STRING_VALUE_MIN

public static final String STRING_VALUE_MIN
See Also:
Constant Field Values
Constructor Detail

ValueAggregatorBaseDescriptor

public ValueAggregatorBaseDescriptor()
Method Detail

generateEntry

public static Map.Entry<Text,Text> generateEntry(String type,
                                                 String id,
                                                 Text val)
Parameters:
type - the aggregation type
id - the aggregation id
val - the val associated with the id to be aggregated
Returns:
an Entry whose key is the aggregation id prefixed with the aggregation type.

generateValueAggregator

public static ValueAggregator generateValueAggregator(String type)
Parameters:
type - the aggregation type
Returns:
a value aggregator of the given type.

configure

public void configure(JobConf job)
get the input file name.

Parameters:
job - a job configuration object


Copyright © 2012 Apache Software Foundation. All Rights Reserved.