org.apache.lucene.search
Class FieldValueHitQueue

java.lang.Object
  org.apache.lucene.util.PriorityQueue<org.apache.lucene.search.FieldValueHitQueue.Entry>
      org.apache.lucene.search.FieldValueHitQueue

public abstract class FieldValueHitQueue
extends PriorityQueue<org.apache.lucene.search.FieldValueHitQueue.Entry>

Expert: A hit queue for sorting by hits by terms in more than one field. Uses FieldCache.DEFAULT for maintaining internal term lookup tables.

Since:

2.9

See Also:

Searcher.search(Query,Filter,int,Sort), FieldCache

WARNING: This API is experimental and might change in incompatible ways in the next release.

Field Summary

protected FieldComparator[]	comparators
protected SortField[]	fields Stores the sort criteria being used.
protected int[]	reverseMul

Method Summary

static FieldValueHitQueue	create(SortField[] fields, int size) Creates a hit queue sorted by the given list of fields.
protected abstract boolean	lessThan(org.apache.lucene.search.FieldValueHitQueue.Entry a, org.apache.lucene.search.FieldValueHitQueue.Entry b) Determines the ordering of objects in this priority queue.

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

add, clear, getHeapArray, getSentinelObject, initialize, insertWithOverflow, pop, size, top, updateTop

Methods inherited from class java.lang.Object

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

Field Detail

fields

protected final SortField[] fields

Stores the sort criteria being used.

comparators

protected final FieldComparator[] comparators

reverseMul

protected final int[] reverseMul

Method Detail

create

public static FieldValueHitQueue create(SortField[] fields,
                                        int size)
                                 throws IOException

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.

Throws:

IOException

lessThan

protected abstract boolean lessThan(org.apache.lucene.search.FieldValueHitQueue.Entry a,
                                    org.apache.lucene.search.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<org.apache.lucene.search.FieldValueHitQueue.Entry>

Returns:

true iff parameter a is less than parameter b.