How to get mapping of query terms to number of their occurrences in a doc?

[Dmitry Goldenberg]

Given a query, I want to be able to, for each query term, get the number of 
occurrences of the term.  I have tried what I'm including below and it does not 
seem to provide reliable results.  Seems to work fine with exact matching but 
as soon as stemming kicks in, all bets are off as to value of the number of 
occurrences returned.
 
Any ideas, anyone?  Can this be written in a simpler and/or more efficient way?
Thanks -
 
      int totalOccurrences = 0;
 
      reader = IndexReader.open(getDirectory(indexDirPath));
      HashSet terms = new HashSet();
      query.extractTerms(terms);
 
      TermFreqVector[] tfvs = reader.getTermFreqVectors(docId);
      if (tfvs != null) {

        // For each term frequency vector (i.e. for each field)
        for (int i = 0; i < tfvs.length; i++) {
          String field = tfvs[i].getField();
          String[] strTerms = tfvs[i].getTerms();
          int[] tfs = tfvs[i].getTermFrequencies();
 
          if (strTerms != null) {

            // For each term in the query
            for (Iterator iter = terms.iterator(); iter.hasNext();) {

              Term term = (Term) iter.next();
              // For each term in the vector
              for (int j = 0; j < strTerms.length; j++) {

                // If found the query term among the vector terms
                if (field.equals(term.field()) && 
strTerms[j].equals(term.text())) {

                  // Add the term frequency to the total
                  totalOccurrences += tfs[j];

                }
              }
            }
          }
        }
      }