+++ /dev/null
-package org.apache.lucene.search;
-
-/**
- * Licensed to the Apache Software Foundation (ASF) under one or more
- * contributor license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership.
- * The ASF licenses this file to You under the Apache License, Version 2.0
- * (the "License"); you may not use this file except in compliance with
- * the License. You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-import java.io.IOException;
-
-import org.apache.lucene.util.PriorityQueue;
-
-/**
- * Expert: A hit queue for sorting by hits by terms in more than one field.
- * Uses <code>FieldCache.DEFAULT</code> for maintaining
- * internal term lookup tables.
- *
- * @lucene.experimental
- * @since 2.9
- * @see Searcher#search(Query,Filter,int,Sort)
- * @see FieldCache
- */
-public abstract class FieldValueHitQueue<T extends FieldValueHitQueue.Entry> extends PriorityQueue<T> {
-
- public static class Entry extends ScoreDoc {
- public int slot;
-
- public Entry(int slot, int doc, float score) {
- super(doc, score);
- this.slot = slot;
- }
-
- @Override
- public String toString() {
- return "slot:" + slot + " " + super.toString();
- }
- }
-
- /**
- * An implementation of {@link FieldValueHitQueue} which is optimized in case
- * there is just one comparator.
- */
- private static final class OneComparatorFieldValueHitQueue<T extends FieldValueHitQueue.Entry> extends FieldValueHitQueue<T> {
-
- private final FieldComparator comparator;
- private final int oneReverseMul;
-
- public OneComparatorFieldValueHitQueue(SortField[] fields, int size)
- throws IOException {
- super(fields);
-
- SortField field = fields[0];
- comparator = field.getComparator(size, 0);
- oneReverseMul = field.reverse ? -1 : 1;
-
- comparators[0] = comparator;
- reverseMul[0] = oneReverseMul;
-
- initialize(size);
- }
-
- /**
- * Returns whether <code>a</code> is less relevant than <code>b</code>.
- * @param a ScoreDoc
- * @param b ScoreDoc
- * @return <code>true</code> if document <code>a</code> should be sorted after document <code>b</code>.
- */
- @Override
- protected boolean lessThan(final Entry hitA, final Entry hitB) {
-
- assert hitA != hitB;
- assert hitA.slot != hitB.slot;
-
- final int c = oneReverseMul * comparator.compare(hitA.slot, hitB.slot);
- if (c != 0) {
- return c > 0;
- }
-
- // avoid random sort order that could lead to duplicates (bug #31241):
- return hitA.doc > hitB.doc;
- }
-
- }
-
- /**
- * An implementation of {@link FieldValueHitQueue} which is optimized in case
- * there is more than one comparator.
- */
- private static final class MultiComparatorsFieldValueHitQueue<T extends FieldValueHitQueue.Entry> extends FieldValueHitQueue<T> {
-
- public MultiComparatorsFieldValueHitQueue(SortField[] fields, int size)
- throws IOException {
- super(fields);
-
- int numComparators = comparators.length;
- for (int i = 0; i < numComparators; ++i) {
- SortField field = fields[i];
-
- reverseMul[i] = field.reverse ? -1 : 1;
- comparators[i] = field.getComparator(size, i);
- }
-
- initialize(size);
- }
-
- @Override
- protected boolean lessThan(final Entry hitA, final Entry hitB) {
-
- assert hitA != hitB;
- assert hitA.slot != hitB.slot;
-
- int numComparators = comparators.length;
- for (int i = 0; i < numComparators; ++i) {
- final int c = reverseMul[i] * comparators[i].compare(hitA.slot, hitB.slot);
- if (c != 0) {
- // Short circuit
- return c > 0;
- }
- }
-
- // avoid random sort order that could lead to duplicates (bug #31241):
- return hitA.doc > hitB.doc;
- }
-
- }
-
- // prevent instantiation and extension.
- private FieldValueHitQueue(SortField[] fields) {
- // When we get here, fields.length is guaranteed to be > 0, therefore no
- // need to check it again.
-
- // All these are required by this class's API - need to return arrays.
- // Therefore even in the case of a single comparator, create an array
- // anyway.
- this.fields = fields;
- int numComparators = fields.length;
- comparators = new FieldComparator[numComparators];
- reverseMul = new int[numComparators];
- }
-
- /**
- * Creates a hit queue sorted by the given list of fields.
- *
- * <p><b>NOTE</b>: The instances returned by this method
- * pre-allocate a full array of length <code>numHits</code>.
- *
- * @param fields
- * SortField array we are sorting by in priority order (highest
- * priority first); cannot be <code>null</code> or empty
- * @param size
- * The number of hits to retain. Must be greater than zero.
- * @throws IOException
- */
- public static <T extends FieldValueHitQueue.Entry> FieldValueHitQueue<T> create(SortField[] fields, int size) throws IOException {
-
- if (fields.length == 0) {
- throw new IllegalArgumentException("Sort must contain at least one field");
- }
-
- if (fields.length == 1) {
- return new OneComparatorFieldValueHitQueue<T>(fields, size);
- } else {
- return new MultiComparatorsFieldValueHitQueue<T>(fields, size);
- }
- }
-
- public FieldComparator[] getComparators() {
- return comparators;
- }
-
- public int[] getReverseMul() {
- return reverseMul;
- }
-
- /** Stores the sort criteria being used. */
- protected final SortField[] fields;
- protected final FieldComparator[] comparators;
- protected final int[] reverseMul;
-
- @Override
- protected abstract boolean lessThan (final Entry a, final Entry b);
-
- /**
- * 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.
- *
- * @param entry The Entry used to create a FieldDoc
- * @return The newly created FieldDoc
- * @see Searchable#search(Weight,Filter,int,Sort)
- */
- FieldDoc fillFields(final Entry entry) {
- final int n = comparators.length;
- final Object[] fields = new Object[n];
- for (int i = 0; i < n; ++i) {
- fields[i] = comparators[i].value(entry.slot);
- }
- //if (maxscore > 1.0f) doc.score /= maxscore; // normalize scores
- return new FieldDoc(entry.doc, entry.score, fields);
- }
-
- /** Returns the SortFields being used by this hit queue. */
- SortField[] getFields() {
- return fields;
- }
-}
fnp / pylucene.git / blobdiff