/** populates a request object (pre-populated with defaults) based on a parser. */
 public static void parseRequest(TermVectorRequest termVectorRequest, XContentParser parser)
     throws IOException {
   XContentParser.Token token;
   String currentFieldName = null;
   List<String> fields = new ArrayList<>();
   while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
     if (token == XContentParser.Token.FIELD_NAME) {
       currentFieldName = parser.currentName();
     } else if (currentFieldName != null) {
       if (currentFieldName.equals("fields")) {
         if (token == XContentParser.Token.START_ARRAY) {
           while (parser.nextToken() != XContentParser.Token.END_ARRAY) {
             fields.add(parser.text());
           }
         } else {
           throw new ElasticsearchParseException(
               "The parameter fields must be given as an array! Use syntax : \"fields\" : [\"field1\", \"field2\",...]");
         }
       } else if (currentFieldName.equals("offsets")) {
         termVectorRequest.offsets(parser.booleanValue());
       } else if (currentFieldName.equals("positions")) {
         termVectorRequest.positions(parser.booleanValue());
       } else if (currentFieldName.equals("payloads")) {
         termVectorRequest.payloads(parser.booleanValue());
       } else if (currentFieldName.equals("term_statistics")
           || currentFieldName.equals("termStatistics")) {
         termVectorRequest.termStatistics(parser.booleanValue());
       } else if (currentFieldName.equals("field_statistics")
           || currentFieldName.equals("fieldStatistics")) {
         termVectorRequest.fieldStatistics(parser.booleanValue());
       } else if ("_index"
           .equals(currentFieldName)) { // the following is important for multi request parsing.
         termVectorRequest.index = parser.text();
       } else if ("_type".equals(currentFieldName)) {
         termVectorRequest.type = parser.text();
       } else if ("_id".equals(currentFieldName)) {
         if (termVectorRequest.doc != null) {
           throw new ElasticsearchParseException(
               "Either \"id\" or \"doc\" can be specified, but not both!");
         }
         termVectorRequest.id = parser.text();
       } else if ("doc".equals(currentFieldName)) {
         if (termVectorRequest.id != null) {
           throw new ElasticsearchParseException(
               "Either \"id\" or \"doc\" can be specified, but not both!");
         }
         termVectorRequest.doc(jsonBuilder().copyCurrentStructure(parser));
       } else if ("_routing".equals(currentFieldName) || "routing".equals(currentFieldName)) {
         termVectorRequest.routing = parser.text();
       } else {
         throw new ElasticsearchParseException(
             "The parameter " + currentFieldName + " is not valid for term vector request!");
       }
     }
   }
   if (fields.size() > 0) {
     String[] fieldsAsArray = new String[fields.size()];
     termVectorRequest.selectedFields(fields.toArray(fieldsAsArray));
   }
 }
  private Fields generateTermVectorsFromDoc(TermVectorRequest request, boolean doAllFields)
      throws IOException {
    // parse the document, at the moment we do update the mapping, just like percolate
    ParsedDocument parsedDocument =
        parseDocument(indexShard.shardId().getIndex(), request.type(), request.doc());

    // select the right fields and generate term vectors
    ParseContext.Document doc = parsedDocument.rootDoc();
    Collection<String> seenFields = new HashSet<>();
    Collection<GetField> getFields = new HashSet<>();
    for (IndexableField field : doc.getFields()) {
      FieldMapper fieldMapper = indexShard.mapperService().smartNameFieldMapper(field.name());
      if (seenFields.contains(field.name())) {
        continue;
      } else {
        seenFields.add(field.name());
      }
      if (!isValidField(fieldMapper)) {
        continue;
      }
      if (request.selectedFields() == null
          && !doAllFields
          && !fieldMapper.fieldType().storeTermVectors()) {
        continue;
      }
      if (request.selectedFields() != null && !request.selectedFields().contains(field.name())) {
        continue;
      }
      String[] values = doc.getValues(field.name());
      getFields.add(new GetField(field.name(), Arrays.asList((Object[]) values)));
    }
    return generateTermVectors(getFields, request.offsets(), request.perFieldAnalyzer());
  }
  public TermVectorResponse getTermVector(TermVectorRequest request, String concreteIndex) {
    final Engine.Searcher searcher = indexShard.acquireSearcher("term_vector");
    IndexReader topLevelReader = searcher.reader();
    final TermVectorResponse termVectorResponse =
        new TermVectorResponse(concreteIndex, request.type(), request.id());

    final Term uidTerm =
        new Term(UidFieldMapper.NAME, Uid.createUidAsBytes(request.type(), request.id()));
    Engine.GetResult get = indexShard.get(new Engine.Get(request.realtime(), uidTerm));
    boolean docFromTranslog = get.source() != null;
    AggregatedDfs dfs = null;

    /* fetched from translog is treated as an artificial document */
    if (docFromTranslog) {
      request.doc(get.source().source, false);
      termVectorResponse.setDocVersion(get.version());
    }

    /* handle potential wildcards in fields */
    if (request.selectedFields() != null) {
      handleFieldWildcards(request);
    }

    try {
      Fields topLevelFields = MultiFields.getFields(topLevelReader);
      Versions.DocIdAndVersion docIdAndVersion = get.docIdAndVersion();
      /* from an artificial document */
      if (request.doc() != null) {
        Fields termVectorsByField = generateTermVectorsFromDoc(request, !docFromTranslog);
        // if no document indexed in shard, take the queried document itself for stats
        if (topLevelFields == null) {
          topLevelFields = termVectorsByField;
        }
        if (termVectorsByField != null && useDfs(request)) {
          dfs = getAggregatedDfs(termVectorsByField, request);
        }
        termVectorResponse.setFields(
            termVectorsByField, request.selectedFields(), request.getFlags(), topLevelFields, dfs);
        termVectorResponse.setExists(true);
        termVectorResponse.setArtificial(!docFromTranslog);
      }
      /* or from an existing document */
      else if (docIdAndVersion != null) {
        // fields with stored term vectors
        Fields termVectorsByField =
            docIdAndVersion.context.reader().getTermVectors(docIdAndVersion.docId);
        Set<String> selectedFields = request.selectedFields();
        // generate tvs for fields where analyzer is overridden
        if (selectedFields == null && request.perFieldAnalyzer() != null) {
          selectedFields = getFieldsToGenerate(request.perFieldAnalyzer(), termVectorsByField);
        }
        // fields without term vectors
        if (selectedFields != null) {
          termVectorsByField =
              addGeneratedTermVectors(get, termVectorsByField, request, selectedFields);
        }
        if (termVectorsByField != null && useDfs(request)) {
          dfs = getAggregatedDfs(termVectorsByField, request);
        }
        termVectorResponse.setFields(
            termVectorsByField, request.selectedFields(), request.getFlags(), topLevelFields, dfs);
        termVectorResponse.setDocVersion(docIdAndVersion.version);
        termVectorResponse.setExists(true);
      } else {
        termVectorResponse.setExists(false);
      }
    } catch (Throwable ex) {
      throw new ElasticsearchException("failed to execute term vector request", ex);
    } finally {
      searcher.close();
      get.release();
    }
    return termVectorResponse;
  }