package org.apache.lucene.search.spans;
import java.io.IOException;
import java.util.Objects;
import org.apache.lucene.search.DocIdSetIterator;
import org.apache.lucene.search.LeafSimScorer;
import org.apache.lucene.search.Scorer;
import org.apache.lucene.search.TwoPhaseIterator;
public class SpanScorer extends Scorer {
protected final Spans spans;
protected final LeafSimScorer docScorer;
private float freq;
private int numMatches;
private int lastScoredDoc = -1;
public SpanScorer(SpanWeight weight, Spans spans, LeafSimScorer docScorer) {
super(weight);
this.spans = Objects.requireNonNull(spans);
this.docScorer = docScorer;
}
public Spans getSpans() {
return spans;
}
@Override
public int docID() {
return spans.docID();
}
@Override
public DocIdSetIterator iterator() {
return spans;
}
@Override
public TwoPhaseIterator twoPhaseIterator() {
return spans.asTwoPhaseIterator();
}
protected float scoreCurrentDoc() throws IOException {
assert docScorer != null : getClass() + " has a null docScorer!";
return docScorer.score(docID(), freq);
}
protected final void setFreqCurrentDoc() throws IOException {
freq = 0.0f;
numMatches = 0;
spans.doStartCurrentDoc();
assert spans.startPosition() == -1 : "incorrect initial start position, " + spans;
assert spans.endPosition() == -1 : "incorrect initial end position, " + spans;
int prevStartPos = -1;
int prevEndPos = -1;
int startPos = spans.nextStartPosition();
assert startPos != Spans.NO_MORE_POSITIONS : "initial startPos NO_MORE_POSITIONS, " + spans;
do {
assert startPos >= prevStartPos;
int endPos = spans.endPosition();
assert endPos != Spans.NO_MORE_POSITIONS;
assert (startPos != prevStartPos) || (endPos >= prevEndPos) : "decreased endPos="+endPos;
numMatches++;
if (docScorer == null) {
freq = 1;
return;
}
freq += (1.0 / (1.0 + spans.width()));
spans.doCurrentSpans();
prevStartPos = startPos;
prevEndPos = endPos;
startPos = spans.nextStartPosition();
} while (startPos != Spans.NO_MORE_POSITIONS);
assert spans.startPosition() == Spans.NO_MORE_POSITIONS : "incorrect final start position, " + spans;
assert spans.endPosition() == Spans.NO_MORE_POSITIONS : "incorrect final end position, " + spans;
}
private void ensureFreq() throws IOException {
int currentDoc = docID();
if (lastScoredDoc != currentDoc) {
setFreqCurrentDoc();
lastScoredDoc = currentDoc;
}
}
@Override
public final float score() throws IOException {
ensureFreq();
return scoreCurrentDoc();
}
@Override
public float getMaxScore(int upTo) throws IOException {
return Float.POSITIVE_INFINITY;
}
final float sloppyFreq() throws IOException {
ensureFreq();
return freq;
}
}