org.apache.lucene.search

Class FieldValueHitQueue<T extends FieldValueHitQueue.Entry>

java.lang.Object

org.apache.lucene.util.PriorityQueue<T>

org.apache.lucene.search.FieldValueHitQueue<T>

All Implemented Interfaces:

java.lang.Iterable<T>

Direct Known Subclasses:

FieldValueHitQueue.MultiComparatorsFieldValueHitQueue, FieldValueHitQueue.OneComparatorFieldValueHitQueue

public abstract class FieldValueHitQueue<T extends FieldValueHitQueue.Entry>
extends PriorityQueue<T>

Expert: A hit queue for sorting by hits by terms in more than one field.

Since:

2.9

See Also:

IndexSearcher.search(Query,int,Sort)

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	FieldValueHitQueue.Entry Extension of ScoreDoc to also store the FieldComparator slot.
private static class	FieldValueHitQueue.MultiComparatorsFieldValueHitQueue<T extends FieldValueHitQueue.Entry> An implementation of FieldValueHitQueue which is optimized in case there is more than one comparator.
private static class	FieldValueHitQueue.OneComparatorFieldValueHitQueue<T extends FieldValueHitQueue.Entry> An implementation of FieldValueHitQueue which is optimized in case there is just one comparator.

Field Summary

Fields

Modifier and Type	Field and Description
protected FieldComparator<?>[]	comparators
protected SortField[]	fields Stores the sort criteria being used.
protected int[]	reverseMul

Constructor Summary

Constructors

Modifier	Constructor and Description
private	FieldValueHitQueue(SortField[] fields, int size)

Method Summary

Modifier and Type	Method and Description
static <T extends FieldValueHitQueue.Entry> FieldValueHitQueue<T>	create(SortField[] fields, int size) Creates a hit queue sorted by the given list of fields.
(package private) FieldDoc	fillFields(FieldValueHitQueue.Entry entry) Given a queue Entry, creates a corresponding FieldDoc that contains the values used to sort the given document.
FieldComparator<?>[]	getComparators()
LeafFieldComparator[]	getComparators(LeafReaderContext context)
(package private) SortField[]	getFields() Returns the SortFields being used by this hit queue.
int[]	getReverseMul()
protected abstract boolean	lessThan(FieldValueHitQueue.Entry a, FieldValueHitQueue.Entry b) Determines the ordering of objects in this priority queue.

Methods inherited from class org.apache.lucene.util.PriorityQueue

add, clear, getHeapArray, insertWithOverflow, iterator, pop, remove, size, top, updateTop, updateTop

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Field Detail

fields

protected final SortField[] fields

Stores the sort criteria being used.

comparators

protected final FieldComparator<?>[] comparators

reverseMul

protected final int[] reverseMul

Constructor Detail

FieldValueHitQueue

private FieldValueHitQueue(SortField[] fields,
                           int size)

Method Detail

create

public static <T extends FieldValueHitQueue.Entry> FieldValueHitQueue<T> create(SortField[] fields,
                                                                                int size)

Creates a hit queue sorted by the given list of fields.

NOTE: The instances returned by this method pre-allocate a full array of length numHits.

Parameters:

fields - SortField array we are sorting by in priority order (highest priority first); cannot be null or empty

size - The number of hits to retain. Must be greater than zero.

getComparators

public FieldComparator<?>[] getComparators()

getReverseMul

public int[] getReverseMul()

getComparators

public LeafFieldComparator[] getComparators(LeafReaderContext context)
                                     throws java.io.IOException

Throws:

java.io.IOException

lessThan

protected abstract boolean lessThan(FieldValueHitQueue.Entry a,
                                    FieldValueHitQueue.Entry b)

Description copied from class: PriorityQueue

Determines the ordering of objects in this priority queue. Subclasses must define this one method.

Specified by:

lessThan in class PriorityQueue<T extends FieldValueHitQueue.Entry>

Returns:

true iff parameter a is less than parameter b.

fillFields

FieldDoc fillFields(FieldValueHitQueue.Entry entry)

Given a queue Entry, creates a corresponding FieldDoc that contains the values used to sort the given document. These values are not the raw values out of the index, but the internal representation of them. This is so the given search hit can be collated by a MultiSearcher with other search hits.

Parameters:

entry - The Entry used to create a FieldDoc

Returns:

The newly created FieldDoc

See Also:

IndexSearcher.search(Query,int,Sort)

getFields

SortField[] getFields()

Returns the SortFields being used by this hit queue.