How to use

freq

method

in

org.apache.lucene.index.PostingsEnum

@Override
float maxFreq() throws IOException {
 // every term position in each postings list can be at the head of at most
 // one matching phrase, so the maximum possible phrase freq is the sum of
 // the freqs of the postings lists.
 float maxFreq = 0;
 for (PhrasePositions phrasePosition : phrasePositions) {
  maxFreq += phrasePosition.postings.freq();
 }
 return maxFreq;
}

/**
 * Create a new {@link TermMatchesIterator} for the given term and postings list
 */
TermMatchesIterator(Query query, PostingsEnum pe) throws IOException {
 this.pe = pe;
 this.query = query;
 this.upto = pe.freq();
}

@Override
public void reset() throws IOException {
 for (PostingsAndPosition posting : postings) {
  posting.freq = posting.postings.freq();
  posting.pos = -1;
  posting.upTo = 0;
 }
}

@Override
public int freq() throws IOException {
 assert current != null;
 return current.freq();
}

@Override
public int freq() throws IOException {
 return in.freq();
}

@Override
public int freq() throws IOException {
 return current.postings.freq();
}

final int freq() throws IOException {
 return postingsEnum.freq();
}

final void firstPosition() throws IOException {
  count = postings.freq();  // read first pos
  nextPosition();
}

@Override
public int advance(int target) throws IOException {
 assert target > doc;
 doc = postings.advance(target);
 if (doc != DocIdSetIterator.NO_MORE_DOCS) {
  freq = postings.freq();
  assert freq >= 1;
  count = 0;
 }
 position = -1;
 return doc;
}

@Override
public int nextDoc() throws IOException {
 doc = postings.nextDoc();
 if (doc != DocIdSetIterator.NO_MORE_DOCS) {
  freq = postings.freq();
  assert freq >= 1;
  count = 0;
 }
 position = -1;
 return doc;
}

final void firstPosition() throws IOException {
 count = postings.freq();  // read first pos
 nextPosition();
}

@Override
public float score() throws IOException {
 assert docID() != DocIdSetIterator.NO_MORE_DOCS;
 return docScorer.score(postingsEnum.docID(), postingsEnum.freq());
}

@Override
public int freq() throws IOException {
 int doc = docID();
 if (doc == posQueueDoc) {
  return freq;
 }
 freq = 0;
 started = false;
 posQueue.clear();
 for (PostingsAndPosition pp : subs) {
  if (pp.pe.docID() == doc) {
   pp.pos = pp.pe.nextPosition();
   pp.upto = pp.pe.freq();
   posQueue.add(pp);
   freq += pp.upto;
  }
 }
 return freq;
}

private int getPhraseScore(final ComplexQueryData data, final int docBase, final PostingsEnum postingsEnum)
    throws IOException {
  int weight = 0;
  while (postingsEnum.nextDoc() != DocIdSetIterator.NO_MORE_DOCS) {
    int docId = postingsEnum.docID();
    if (data.documentIds.has(docBase + docId)) {
      IntsHolder positions = data.scorer.getPositions(docBase + docId);
      if (positions == null) {
        continue;
      }
      int freq = postingsEnum.freq();
      for (int i = 0; i < freq; i++) {
        int pos = postingsEnum.nextPosition();
        if (positions.has(pos)) {
          weight++;
        }
      }
    }
  }
  return weight;
}

posting.freq = posting.postings.freq();
posting.pos = posting.postings.nextPosition();
posting.upTo = 1;

@Override
public int freq() throws IOException {
 int doc = docID();
 if (doc != posQueueDoc) {
  posQueue.clear();
  for (PostingsEnum sub : subs) {
   if (sub.docID() == doc) {
    int freq = sub.freq();
    for (int i = 0; i < freq; i++) {
     posQueue.add(sub.nextPosition());
    }
   }
  }
  posQueue.sort();
  posQueueDoc = doc;
 }
 return posQueue.size();
}

private void addPositions(final PostingsEnum in, final IndexOutput out) throws IOException {
 int freq = in.freq();
 out.writeVInt(freq);
 int previousPosition = 0;
 int previousEndOffset = 0;
 for (int i = 0; i < freq; i++) {
  final int pos = in.nextPosition();
  final BytesRef payload = in.getPayload();
  // The low-order bit of token is set only if there is a payload, the
  // previous bits are the delta-encoded position.
  final int token = (pos - previousPosition) << 1 | (payload == null ? 0 : 1);
  out.writeVInt(token);
  previousPosition = pos;
  if (storeOffsets) { // don't encode offsets if they are not stored
   final int startOffset = in.startOffset();
   final int endOffset = in.endOffset();
   out.writeVInt(startOffset - previousEndOffset);
   out.writeVInt(endOffset - startOffset);
   previousEndOffset = endOffset;
  }
  if (payload != null) {
   out.writeVInt(payload.length);
   out.writeBytes(payload.bytes, payload.offset, payload.length);
  }
 }
}

@Override
public Explanation explain(LeafReaderContext context, int doc) throws IOException {
 String desc = "weight(" + getQuery() + " in " + doc + ") [" + function + "]";
 Terms terms = context.reader().terms(fieldName);
 if (terms == null) {
  return Explanation.noMatch(desc + ". Field " + fieldName + " doesn't exist.");
 }
 TermsEnum termsEnum = terms.iterator();
 if (termsEnum.seekExact(new BytesRef(featureName)) == false) {
  return Explanation.noMatch(desc + ". Feature " + featureName + " doesn't exist.");
 }
 PostingsEnum postings = termsEnum.postings(null, PostingsEnum.FREQS);
 if (postings.advance(doc) != doc) {
  return Explanation.noMatch(desc + ". Feature " + featureName + " isn't set.");
 }
 return function.explain(fieldName, featureName, boost, doc, postings.freq());
}

freqs[i] = in.freq();
++i;

int freq;
if (writeFreqs) {
 freq = postingsEnum.freq();
 totalTermFreq += freq;
} else {