Package org.apache.accumulo.core.client.summary.summarizers

Class FamilySummarizer

java.lang.Object

org.apache.accumulo.core.client.summary.CountingSummarizer<ByteSequence>

org.apache.accumulo.core.client.summary.summarizers.FamilySummarizer

All Implemented Interfaces:

Summarizer

public class FamilySummarizer
extends CountingSummarizer<ByteSequence>

Counts column column families. Leverages super class to defend against too many. This class is useful for discovering what column families are present when the expected number of families is small.

Since:

2.0.0

See Also:

TableOperations.addSummarizers(String, org.apache.accumulo.core.client.summary.SummarizerConfiguration...), TableOperations.summaries(String)

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.accumulo.core.client.summary.CountingSummarizer

CountingSummarizer.Converter<K>

Nested classes/interfaces inherited from interface org.apache.accumulo.core.client.summary.Summarizer

Summarizer.Collector, Summarizer.Combiner, Summarizer.StatisticConsumer

Field Summary

Fields inherited from class org.apache.accumulo.core.client.summary.CountingSummarizer

COUNTER_STAT_PREFIX, DELETES_IGNORED_STAT, EMITTED_STAT, INGNORE_DELETES_DEFAULT, INGNORE_DELETES_OPT, MAX_CKL_DEFAULT, MAX_COUNTER_DEFAULT, MAX_COUNTER_LEN_OPT, MAX_COUNTERS_OPT, SEEN_STAT, TOO_LONG_STAT, TOO_MANY_STAT

Constructor Summary

Constructors

Constructor	Description
FamilySummarizer()

Method Summary

Modifier and Type	Method	Description
protected CountingSummarizer.Converter<ByteSequence>	converter()
protected UnaryOperator<ByteSequence>	copier()	Override this if your key type is mutable and subject to change.

Methods inherited from class org.apache.accumulo.core.client.summary.CountingSummarizer

collector, combiner, encoder

Methods inherited from class java.lang.Object

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

Constructor Detail

FamilySummarizer

public FamilySummarizer()

Method Detail

copier

protected UnaryOperator<ByteSequence> copier()

Description copied from class: CountingSummarizer

Override this if your key type is mutable and subject to change.

Overrides:

copier in class CountingSummarizer<ByteSequence>

Returns:

a function that used to copy the counter object. This function is only used when the collector has never seen the counter object before. In this case the collector needs to possibly copy the counter object before using as map key. The default implementation is the UnaryOperator.identity() function.

converter

protected CountingSummarizer.Converter<ByteSequence> converter()

Specified by:

converter in class CountingSummarizer<ByteSequence>

Returns:

A function that is used to convert each key value to zero or more counter objects. Each function returned should be independent.