@SuppressWarnings("unchecked")
 @Override
 public List<String> getClusterByCarrotVersion2(String query) {
   // TODO Auto-generated method stub
   List<String> strs = new ArrayList<String>();
   final Controller controller = ControllerFactory.createPooling();
   final Map<String, Object> luceneGlobalAttributes = new HashMap<String, Object>();
   LuceneDocumentSourceDescriptor.attributeBuilder(luceneGlobalAttributes).directory(directory);
   SimpleFieldMapperDescriptor.attributeBuilder(luceneGlobalAttributes)
       .titleField(TITLE_FIELD)
       .contentField(CONTENTS_FIELD)
       .searchFields(Arrays.asList(new String[] {TITLE_FIELD, CONTENTS_FIELD}));
   controller.init(
       new HashMap<String, Object>(),
       new ProcessingComponentConfiguration(
           LuceneDocumentSource.class, "lucene", luceneGlobalAttributes));
   final Map<String, Object> processingAttributes = Maps.newHashMap();
   CommonAttributesDescriptor.attributeBuilder(processingAttributes).query(query);
   ProcessingResult process =
       controller.process(
           processingAttributes, "lucene", LingoClusteringAlgorithm.class.getName());
   for (Cluster c : process.getClusters()) {
     strs.add(c.getLabel() + " >>>> " + c.getAllDocuments().size());
   }
   return strs;
 }
  public static void main(String[] args) throws IOException {
    /*
     * We will use the CachingController for this example. Running
     * LuceneDocumentSource within the CachingController will let us open the index
     * once per component initialization and not once per query, which would be the
     * case with SimpleController. We will also use this opportunity to show how
     * component-specific attribute values can be passed during CachingComponent
     * initialization.
     */

    /*
     * Create a caching controller that will reuse processing component instances, but
     * will not perform any caching of results produced by components. We will leave
     * caching of documents from Lucene index to Lucene and the operating system
     * caches.
     */
    final Controller controller = ControllerFactory.createPooling();

    /*
     * Prepare a map with component-specific attributes. Here, this map will contain
     * the index location and names of fields to be used to fetch document title and
     * summary.
     */
    final Map<String, Object> luceneGlobalAttributes = new HashMap<String, Object>();

    String indexPath = "put your index path here or pass as the first argument";
    if (args.length == 1) {
      indexPath = args[0];
    }

    LuceneDocumentSourceDescriptor.attributeBuilder(luceneGlobalAttributes)
        .directory(FSDirectory.open(new File(indexPath)));

    /*
     * Specify fields providing data inside your Lucene index.
     */
    SimpleFieldMapperDescriptor.attributeBuilder(luceneGlobalAttributes)
        .titleField("title")
        .contentField("snippet")
        .searchFields(Arrays.asList(new String[] {"titleField", "fullContent"}));

    /*
     * Initialize the controller passing the above attributes as component-specific
     * for Lucene. The global attributes map will be empty. Note that we've provided
     * an identifier for our specially-configured Lucene component, we'll need to use
     * this identifier when performing processing.
     */
    controller.init(
        new HashMap<String, Object>(),
        new ProcessingComponentConfiguration(
            LuceneDocumentSource.class, "lucene", luceneGlobalAttributes));

    /*
     * Perform processing.
     */
    String query = "mining";
    final Map<String, Object> processingAttributes = Maps.newHashMap();
    CommonAttributesDescriptor.attributeBuilder(processingAttributes).query(query);

    /*
     * We need to refer to the Lucene component by its identifier we set during
     * initialization. As we've not assigned any identifier to the
     * LingoClusteringAlgorithm we want to use, we can its fully qualified class name.
     */
    ProcessingResult process =
        controller.process(
            processingAttributes, "lucene", LingoClusteringAlgorithm.class.getName());

    ConsoleFormatter.displayResults(process);
  }