Package com.atlassian.jira.issue.search.parameters.lucene.sort

Class JiraLuceneFieldFinder

java.lang.Object

com.atlassian.jira.issue.search.parameters.lucene.sort.JiraLuceneFieldFinder

@Internal
public class JiraLuceneFieldFinder
extends Object

This used to be a cache of values but it was found that it consumed a hell of a lot of memory for no benefit (JRA-10111). So the cache.put was never called.

This has been refactored into a "finder" of terms values for fields within documents.

Platform-specific class intended for the Lucene search platform only.

Jira Search exposes a common API backed by multiple search engines. This class bypasses that abstraction and couples callers to Lucene internals.

Using this class when the runtime search platform is not Lucene (e.g. OpenSearch) may produce incorrect results or failures.

Internal use only.

Constructor Summary

Constructors

Constructor	Description
JiraLuceneFieldFinder()

Method Summary

Modifier and Type	Method	Description
Object[]	getCustom(org.apache.lucene.index.IndexReader reader, String field, MappedSortComparator mappedSortComparator)	This is used to retrieve values from the Lucence index.
static JiraLuceneFieldFinder	getInstance()
Collection<String>[]	getMatches(org.apache.lucene.index.IndexReader reader, String field)	For each document in the index, it returns an array of string collections for each matching term.
void	getMatches(org.apache.lucene.index.IndexReader reader, String field, MatchHandler handler)	For each document that has at least one value defined for the specified field, invokes MatchHandler.handleMatchedDocument(int, String) with the document index and the field value as the argument.
List<String>	getTermValuesForField(org.apache.lucene.index.IndexReader reader, String field)	This method is used to retrieve term values form the Lucene index.
List<String>[]	getUniqueMatches(org.apache.lucene.index.IndexReader reader, String field)	For each document in the index, it returns an array of string collections for each matching term.

Methods inherited from class java.lang.Object

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

Constructor Details

JiraLuceneFieldFinder

public JiraLuceneFieldFinder()

Method Details

getInstance

public static JiraLuceneFieldFinder getInstance()

getCustom

public Object[] getCustom(org.apache.lucene.index.IndexReader reader,
 String field,
 MappedSortComparator mappedSortComparator)
                   throws IOException

This is used to retrieve values from the Lucence index. It returns an array that is the same size as the number of documents in the reader and will have all null values if the field is not present, otherwise it has the values of the field within the document.

Parameters:

reader - the Lucence index reader

field - the name of the field to find

mappedSortComparator - the MappedSortComparator that we are acting on behalf of

Returns:

an non null array of values, which may contain null values.

Throws:

IOException - if things dont play out well.

getTermValuesForField

public List<String> getTermValuesForField(org.apache.lucene.index.IndexReader reader,
 String field)
                                   throws IOException

This method is used to retrieve term values form the Lucene index. It returns a list of the text representation of the terms that are present in a field - this list will be empty if a field has no terms.

Parameters:

reader - the Lucence index reader

field - the name of the field to find

Returns:

a List of strings that represent the term values for a specified field

Throws:

IOException

getMatches

public Collection<String>[] getMatches(org.apache.lucene.index.IndexReader reader,
 String field)
                                throws IOException

For each document in the index, it returns an array of string collections for each matching term. Uses the DefaultMatchHandler.

Parameters:

reader - the index to read

field - the field to check the documents for

Returns:

an array of string collections for each term for each document

Throws:

IOException - if things dont play out well.

getUniqueMatches

@ExperimentalApi
public List<String>[] getUniqueMatches(org.apache.lucene.index.IndexReader reader,
 String field)
                                throws IOException

For each document in the index, it returns an array of string collections for each matching term. Uses the SingleValueMatchHandler, so any collections that are returned are guaranteed to contain exactly one (possibly null) value in them.

Parameters:

reader - the index to read

field - the field to check the documents for

Returns:

an array of string collections for each term for each document

Throws:

IOException - if things dont play out well.

getMatches

@ExperimentalApi
public void getMatches(org.apache.lucene.index.IndexReader reader,
 String field,
 MatchHandler handler)
                throws IOException

For each document that has at least one value defined for the specified field, invokes MatchHandler.handleMatchedDocument(int, String) with the document index and the field value as the argument.

Parameters:

reader - the index to read

field - the field to check the documents for

handler - a handler that will be invoked for each matching term

Throws:

IOException - if things dont play out well.