com.atlassian.jira.issue.search.parameters.lucene.sort
Class MappedSortComparator

java.lang.Object
  org.apache.lucene.search.FieldComparatorSource
      com.atlassian.jira.issue.search.parameters.lucene.sort.MappedSortComparator

All Implemented Interfaces:

Serializable

public class MappedSortComparator
extends org.apache.lucene.search.FieldComparatorSource

This Sort Comparator reads through the terms dictionary in lucene, and builds up a list of ordered terms. It then sorts the documents according to the order that they appear in the terms list.

This approach, whilst very fast, does load the entire term dictionary into memory. This could be a problem where there are a large number of terms (eg. text fields). The CPU and memory usage is also proportional to the number of issues. We are currently calculating this on every Issue Navigator request. This is surely a limiting factor in the number of issues JIRA can handle.

See Also:

Serialized Form

Nested Class Summary

class

MappedSortComparator.InternalFieldComparator

Constructor Summary

MappedSortComparator(LuceneFieldSorter sorter)

Method Summary

boolean	equals(Object o)
Object	getComparable(String termtext) Returns an object which, when sorted according by the comparator returned from LuceneFieldSorter.getComparator() , will order the Term values in the correct order.
Comparator	getComparator()
int	hashCode()
org.apache.lucene.search.FieldComparator	newComparator(String fieldname, int numHits, int sortPos, boolean reversed)

Methods inherited from class java.lang.Object

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

Constructor Detail

MappedSortComparator

public MappedSortComparator(LuceneFieldSorter sorter)

Method Detail

newComparator

public org.apache.lucene.search.FieldComparator newComparator(String fieldname,
                                                              int numHits,
                                                              int sortPos,
                                                              boolean reversed)
                                                       throws IOException

Specified by:

newComparator in class org.apache.lucene.search.FieldComparatorSource

Throws:

IOException

getComparable

public Object getComparable(String termtext)

Returns an object which, when sorted according by the comparator returned from LuceneFieldSorter.getComparator() , will order the Term values in the correct order.

For example, if the Terms contained integer values, this method would return new Integer(termtext). Note that this might not always be the most efficient implementation - for this particular example, a better implementation might be to make a ScoreDocLookupComparator that uses an internal lookup table of int.

Parameters:

termtext - The textual value of the term.

Returns:

An object representing termtext that can be sorted by LuceneFieldSorter.getComparator()

See Also:

Comparable, MappedSortComparator.InternalFieldComparator

getComparator

public Comparator getComparator()

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object