public class WordCount {

     static Directory directory;

     // 创建分词器

     static Analyzer analyzer = new IKAnalyzer();

     static IndexWriterConfig config = new IndexWriterConfig(analyzer);

     static IndexWriter writer;

     static IndexReader reader;

     static {

         // 指定索引存放目录以及配置参数

         try {

             directory = FSDirectory.open(Paths.get("F:/luceneIndex"));

             writer = new IndexWriter(directory, config);

         } catch (IOException e) {

             e.printStackTrace();

         }

     }

     public static void main(String[] args) {

         indexCreate();

         Map<String, Long> map = getTotalFreqMap();

         Map<String, Long> sortMap = sortMapByValue(map);

         Set<Entry<String, Long>> entrySet = sortMap.entrySet();

         Iterator<Entry<String, Long>> iterator = entrySet.iterator();

         while (iterator.hasNext()) {

             Entry<String, Long> entry = iterator.next();

             System.out.println(entry.getKey() + "----" + entry.getValue());

         }

     }

     /**

      * 创建索引

      */

     public static void indexCreate() {

         // 文件夹检测(创建索引前要保证目录是空的)

         File file = new File("f:/luceneIndex");

         if (!file.exists()) {

             file.mkdirs();

         } else {

             try {

                 file.delete();

             } catch (Exception e) {

                 e.printStackTrace();

             }

         }

         // 将采集的数据封装到Document中

         Document doc = new Document();

         FieldType ft = new FieldType();

         ft.setIndexOptions(IndexOptions.DOCS_AND_FREQS);

         ft.setStored(true);

         ft.setStoreTermVectors(true);

         ft.setTokenized(true);

         // ft.setStoreTermVectorOffsets(true);

         // ft.setStoreTermVectorPositions(true);

         // 读取文件内容(小文件,readFully)

         File content = new File("f:/qz/twitter.txt");

         try {

             byte[] buffer = new byte[(int) content.length()];

             IOUtils.readFully(new FileInputStream(content), buffer);

             doc.add(new Field("twitter", new String(buffer), ft));

         } catch (Exception e) {

             e.printStackTrace();

         }

         // 生成索引

         try {

             writer.addDocument(doc);

             // 关闭

             writer.close();

         } catch (IOException e) {

             e.printStackTrace();

         }

     }

     /**

      * 获得词频map

      *

      * @throws ParseException

      */

     public static Map<String, Long> getTotalFreqMap() {

         Map<String, Long> map = new HashMap<String, Long>();

         try {

             reader = DirectoryReader.open(directory);

             List<LeafReaderContext> leaves = reader.leaves();

             for (LeafReaderContext leafReaderContext : leaves) {

                 LeafReader leafReader = leafReaderContext.reader();

                 Terms terms = leafReader.terms("twitter");

                 TermsEnum iterator = terms.iterator();

                 BytesRef term = null;

                 while ((term = iterator.next()) != null) {

                     String text = term.utf8ToString();

                     map.put(text, iterator.totalTermFreq());

                 }

             }

             reader.close();

             return map;

         } catch (IOException e) {

             e.printStackTrace();

         }

         return null;

     }

     /**

      * 使用 Map按value进行排序

      *

      * @param map

      * @return

      */

     public static Map<String, Long> sortMapByValue(Map<String, Long> oriMap) {

         if (oriMap == null || oriMap.isEmpty()) {

             return null;

         }

         Map<String, Long> sortedMap = new LinkedHashMap<String, Long>();

         List<Map.Entry<String, Long>> entryList = new ArrayList<Map.Entry<String, Long>>(oriMap.entrySet());

         Collections.sort(entryList, new MapValueComparator());

         Iterator<Map.Entry<String, Long>> iter = entryList.iterator();

         Map.Entry<String, Long> tmpEntry = null;

         while (iter.hasNext()) {

             tmpEntry = iter.next();

             sortedMap.put(tmpEntry.getKey(), tmpEntry.getValue());

         }

         return sortedMap;

     }

 }

 class MapValueComparator implements Comparator<Map.Entry<String, Long>> {

     @Override

     public int compare(Entry<String, Long> me1, Entry<String, Long> me2) {

         if (me1.getValue() == me2.getValue()) {

             return ;

         }

         return me1.getValue() > me2.getValue() ? - : ;

         // return me1.getValue().compareTo(me2.getValue());

     }

 }