@Override
  public boolean reload(String collectionName, int docNum) {
    if (collectionName == null) return false;

    CrescentCollectionHandler collectionHandler =
        SpringApplicationContext.getBean(
            "crescentCollectionHandler", CrescentCollectionHandler.class);
    CrescentCollection collection =
        collectionHandler.getCrescentCollections().getCrescentCollection(collectionName);

    if (collection == null) {
      logger.debug("doesn't Collection Info => {}", collectionName);
      return false;
    }

    List<String> fieldName = new ArrayList<String>();
    List<String> flag = new ArrayList<String>();
    List<String> norm = new ArrayList<String>();
    List<String> value = new ArrayList<String>();

    try {
      Directory directory = FSDirectory.open(new File(collection.getIndexingDirectory()));
      IndexReader reader = IndexReader.open(directory);

      Document document = null;
      try {
        document = reader.document(docNum);
      } catch (IllegalArgumentException e) {
        e.printStackTrace();
        return false;
      }

      String fName = null;
      for (Fieldable field : document.getFields()) {
        fName = field.name();
        fieldName.add(fName);
        flag.add(fieldFlag(field));
        if (reader.hasNorms(fName)) {
          norm.add(String.valueOf(Similarity.decodeNorm(reader.norms(fName)[docNum])));
        } else {
          norm.add("---");
        }
        value.add(field.stringValue());
      }

    } catch (IOException e) {
      e.printStackTrace();
      return false;
    }

    result.put("collection", collectionName);
    result.put("docNum", docNum);
    result.put("fieldName", fieldName);
    result.put("flag", flag);
    result.put("norm", norm);
    result.put("value", value);

    return true;
  }
    public Explanation explain(IndexReader reader, int doc) throws IOException {
      ComplexExplanation result = new ComplexExplanation();
      result.setDescription("weight(" + getQuery() + " in " + doc + "), product of:");

      Explanation idfExpl = new Explanation(idf, "idf(docFreq=" + reader.docFreq(term) + ")");

      // explain query weight
      Explanation queryExpl = new Explanation();
      queryExpl.setDescription("queryWeight(" + getQuery() + "), product of:");

      Explanation boostExpl = new Explanation(getBoost(), "boost");
      if (getBoost() != 1.0f) queryExpl.addDetail(boostExpl);
      queryExpl.addDetail(idfExpl);

      Explanation queryNormExpl = new Explanation(queryNorm, "queryNorm");
      queryExpl.addDetail(queryNormExpl);

      queryExpl.setValue(boostExpl.getValue() * idfExpl.getValue() * queryNormExpl.getValue());

      result.addDetail(queryExpl);

      // explain field weight
      String field = term.field();
      ComplexExplanation fieldExpl = new ComplexExplanation();
      fieldExpl.setDescription("fieldWeight(" + term + " in " + doc + "), product of:");

      Explanation tfExpl = scorer(reader).explain(doc);
      fieldExpl.addDetail(tfExpl);
      fieldExpl.addDetail(idfExpl);

      Explanation fieldNormExpl = new Explanation();
      byte[] fieldNorms = reader.norms(field);
      float fieldNorm = fieldNorms != null ? Similarity.decodeNorm(fieldNorms[doc]) : 0.0f;
      fieldNormExpl.setValue(fieldNorm);
      fieldNormExpl.setDescription("fieldNorm(field=" + field + ", doc=" + doc + ")");
      fieldExpl.addDetail(fieldNormExpl);

      fieldExpl.setMatch(Boolean.valueOf(tfExpl.isMatch()));
      fieldExpl.setValue(tfExpl.getValue() * idfExpl.getValue() * fieldNormExpl.getValue());

      result.addDetail(fieldExpl);
      result.setMatch(fieldExpl.getMatch());

      // combine them
      result.setValue(queryExpl.getValue() * fieldExpl.getValue());

      if (queryExpl.getValue() == 1.0f) return fieldExpl;

      return result;
    }