SortHashMapExample.java

// puts wordsMap's key and value into ArrayList.
    List<Map.Entry<String, Integer>> listData = 
      new ArrayList<Map.Entry<String, Integer>>(wordsMap.entrySet());

    /**
     * sorts the data based on the order of values by using Comparator class.
     */
    Collections.sort(listData, new Comparator<Map.Entry<String, Integer>>() {
      public int compare(Map.Entry<String, Integer> entry1,
                         Map.Entry<String, Integer> entry2) {
        return (entry2.getValue() - entry1.getValue());
        }
      }
    );

    // Subtracts the amounts of dataList to the amount we want to see.
    listData = listData.subList(0, wordsToPrint);

    // Prints out all keys and values in listData by using lambda expression.
    for (Map.Entry<String, Integer> entry : listData) {
      printWords(entry.getKey());
    }
    commonInBS.close();
    fileInBS.close();
  }
  
    /**
   * prints out the key and value in normalized format.
   * @param {String} word - the key from the sorted listData.
   */
  private static void printWords(String word) {
    System.out.println(word + " : " + wordsMap.get(word));
  }