| package org.apache.lucene.search; |
| |
| /** |
| * Copyright 2004 The Apache Software Foundation |
| * |
| * Licensed 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; |
| |
| final class BooleanScorer extends Scorer { |
| private SubScorer scorers = null; |
| private BucketTable bucketTable = new BucketTable(this); |
| |
| private int maxCoord = 1; |
| private float[] coordFactors = null; |
| |
| private int requiredMask = 0; |
| private int prohibitedMask = 0; |
| private int nextMask = 1; |
| |
| BooleanScorer(Similarity similarity) { |
| super(similarity); |
| } |
| |
| static final class SubScorer { |
| public Scorer scorer; |
| public boolean done; |
| public boolean required = false; |
| public boolean prohibited = false; |
| public HitCollector collector; |
| public SubScorer next; |
| |
| public SubScorer(Scorer scorer, boolean required, boolean prohibited, |
| HitCollector collector, SubScorer next) |
| throws IOException { |
| this.scorer = scorer; |
| this.done = !scorer.next(); |
| this.required = required; |
| this.prohibited = prohibited; |
| this.collector = collector; |
| this.next = next; |
| } |
| } |
| |
| final void add(Scorer scorer, boolean required, boolean prohibited) |
| throws IOException { |
| int mask = 0; |
| if (required || prohibited) { |
| if (nextMask == 0) |
| throw new IndexOutOfBoundsException |
| ("More than 32 required/prohibited clauses in query."); |
| mask = nextMask; |
| nextMask = nextMask << 1; |
| } else |
| mask = 0; |
| |
| if (!prohibited) |
| maxCoord++; |
| |
| if (prohibited) |
| prohibitedMask |= mask; // update prohibited mask |
| else if (required) |
| requiredMask |= mask; // update required mask |
| |
| scorers = new SubScorer(scorer, required, prohibited, |
| bucketTable.newCollector(mask), scorers); |
| } |
| |
| private final void computeCoordFactors() throws IOException { |
| coordFactors = new float[maxCoord]; |
| for (int i = 0; i < maxCoord; i++) |
| coordFactors[i] = getSimilarity().coord(i, maxCoord-1); |
| } |
| |
| private int end; |
| private Bucket current; |
| |
| public int doc() { return current.doc; } |
| |
| public boolean next() throws IOException { |
| boolean more; |
| do { |
| while (bucketTable.first != null) { // more queued |
| current = bucketTable.first; |
| bucketTable.first = current.next; // pop the queue |
| |
| // check prohibited & required |
| if ((current.bits & prohibitedMask) == 0 && |
| (current.bits & requiredMask) == requiredMask) { |
| return true; |
| } |
| } |
| |
| // refill the queue |
| more = false; |
| end += BucketTable.SIZE; |
| for (SubScorer sub = scorers; sub != null; sub = sub.next) { |
| Scorer scorer = sub.scorer; |
| while (!sub.done && scorer.doc() < end) { |
| sub.collector.collect(scorer.doc(), scorer.score()); |
| sub.done = !scorer.next(); |
| } |
| if (!sub.done) { |
| more = true; |
| } |
| } |
| } while (bucketTable.first != null | more); |
| |
| return false; |
| } |
| |
| public float score() throws IOException { |
| if (coordFactors == null) |
| computeCoordFactors(); |
| return current.score * coordFactors[current.coord]; |
| } |
| |
| static final class Bucket { |
| int doc = -1; // tells if bucket is valid |
| float score; // incremental score |
| int bits; // used for bool constraints |
| int coord; // count of terms in score |
| Bucket next; // next valid bucket |
| } |
| |
| /** A simple hash table of document scores within a range. */ |
| static final class BucketTable { |
| public static final int SIZE = 1 << 10; |
| public static final int MASK = SIZE - 1; |
| |
| final Bucket[] buckets = new Bucket[SIZE]; |
| Bucket first = null; // head of valid list |
| |
| private BooleanScorer scorer; |
| |
| public BucketTable(BooleanScorer scorer) { |
| this.scorer = scorer; |
| } |
| |
| public final int size() { return SIZE; } |
| |
| public HitCollector newCollector(int mask) { |
| return new Collector(mask, this); |
| } |
| } |
| |
| static final class Collector extends HitCollector { |
| private BucketTable bucketTable; |
| private int mask; |
| public Collector(int mask, BucketTable bucketTable) { |
| this.mask = mask; |
| this.bucketTable = bucketTable; |
| } |
| public final void collect(final int doc, final float score) { |
| final BucketTable table = bucketTable; |
| final int i = doc & BucketTable.MASK; |
| Bucket bucket = table.buckets[i]; |
| if (bucket == null) |
| table.buckets[i] = bucket = new Bucket(); |
| |
| if (bucket.doc != doc) { // invalid bucket |
| bucket.doc = doc; // set doc |
| bucket.score = score; // initialize score |
| bucket.bits = mask; // initialize mask |
| bucket.coord = 1; // initialize coord |
| |
| bucket.next = table.first; // push onto valid list |
| table.first = bucket; |
| } else { // valid bucket |
| bucket.score += score; // increment score |
| bucket.bits |= mask; // add bits in mask |
| bucket.coord++; // increment coord |
| } |
| } |
| } |
| |
| public boolean skipTo(int target) throws IOException { |
| throw new UnsupportedOperationException(); |
| } |
| |
| public Explanation explain(int doc) throws IOException { |
| throw new UnsupportedOperationException(); |
| } |
| |
| public String toString() { |
| StringBuffer buffer = new StringBuffer(); |
| buffer.append("boolean("); |
| for (SubScorer sub = scorers; sub != null; sub = sub.next) { |
| buffer.append(sub.scorer.toString()); |
| buffer.append(" "); |
| } |
| buffer.append(")"); |
| return buffer.toString(); |
| } |
| |
| |
| } |