com.esri.gpt.catalog.lucene.stats
Class SingleFieldStats

java.lang.Object
  com.esri.gpt.catalog.lucene.stats.SingleFieldStats

public class SingleFieldStats
extends Object

Provides statistics associated with a single field.

Statistics are unavailable until collected.

Statistics provided are:

• the number of documents considered during statistics collection
• the number of documents that contain the field
• the total number of terms indexed for this field across all documents
• the list of frequencies per term for this field

Constructor Summary

SingleFieldStats(String fieldName)
Construct with a supplied field name.

SingleFieldStats(String fieldName, int maxRecords, int minFrequency, int maxFrequency)
Constructs with a supplied field name and min/max thresholds.

Method Summary

void	collectStats(StatsRequest request, IndexReader reader) Executes the collection of statistics.
protected long	determineNumberOfDocsConsidered(IndexReader reader, OpenBitSet documentFilterBitSet) Determines the number of documents considered during stats collection.
long	getNumberOfDocsConsidered() Gets the number of documents considered during stats collection.
protected boolean	getSortByFrequency() Gets the flag indicating whether or not results should be sorted by frequency.
long	getTimeMillis() Gets the execution time.
protected void	setNumberOfDocsConsidered(long count) Sets the number of documents considered during stats collection.
protected void	setTimeMillis(long millis) Sets the execution time.

Methods inherited from class java.lang.Object

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

Constructor Detail

SingleFieldStats

public SingleFieldStats(String fieldName)

Construct with a supplied field name.

Parameters:

fieldName - the field name

SingleFieldStats

public SingleFieldStats(String fieldName,
                        int maxRecords,
                        int minFrequency,
                        int maxFrequency)

Constructs with a supplied field name and min/max thresholds.

Parameters:

fieldName - the field name

maxRecords - the maximum number of records to return

minFrequency - the minimum term frequency to consider

maxFrequency - the maximum term frequency to consider

Method Detail

collectStats

public void collectStats(StatsRequest request,
                         IndexReader reader)
                  throws IOException

Executes the collection of statistics.

Parameters:

request - the active statistics request

reader - the index reader

Throws:

IOException - if an error occurs while communicating with the index

getNumberOfDocsConsidered

public long getNumberOfDocsConsidered()

Gets the number of documents considered during stats collection.

Returns:

the number of documents considered

setNumberOfDocsConsidered

protected void setNumberOfDocsConsidered(long count)

Sets the number of documents considered during stats collection.

Parameters:

count - the number of documents considered

getSortByFrequency

protected boolean getSortByFrequency()

Gets the flag indicating whether or not results should be sorted by frequency.

Returns:

true if results should be sorted by frequency

getTimeMillis

public long getTimeMillis()

Gets the execution time.

Returns:

the execution time (in milliseconds)

setTimeMillis

protected void setTimeMillis(long millis)

Sets the execution time.

Parameters:

millis - the execution time (in milliseconds)

determineNumberOfDocsConsidered

protected long determineNumberOfDocsConsidered(IndexReader reader,
                                               OpenBitSet documentFilterBitSet)

Determines the number of documents considered during stats collection.
If the document filter bitset is not null, the count will be based upon it's cardinality.
Otherwise the count will be based upon the number of docs returned by the reader.

Parameters:

reader - the index reader

documentFilterBitSet - the bitset represing the subset of documents being cosidered

Returns:

the total number of documents