Main.java

   1 import java.io.File;
   2 import java.util.Scanner;
   3 import java.io.IOException;
   4 import java.util.Map;
   5 import java.util.TreeMap;
   6 import java.util.SortedMap;
   7 import java.util.stream.Collectors;
   8
   9 class Main {
  10
  11     /**
  12      * The main() function
  13      * @param String[] args main() function arguments array
  14      */
  15     public static void main(String[] args) {
  16         // default TreeMap comparator keep alphabetical order
  17         // NOTE: words comparaison is case insensitive and punctuation aware
  18         TreeMap<String, Integer> tm = new TreeMap<String, Integer>(new StrComparator());
  19         // NOTE: words comparaison is case sensitive and punctuation aware
  20         //TreeMap<String, Integer> tm = new TreeMap<String, Integer>();
  21         File f = new File("test_file.txt");
  22         try {
  23             Scanner sc = new Scanner(f);
  24             while (sc.hasNext()) {
  25                 String wordCursor = sc.next();
  26                 Integer count = tm.get(wordCursor);
  27                 if (count == null) {
  28                     count = 0;
  29                 }
  30                 tm.put(wordCursor, count + 1);
  31             }
  32             sc.close();
  33         }
  34         catch (IOException e) {
  35             e.printStackTrace();
  36         }
  37
  38         System.out.println("TreeMap full content:");
  39         for (String wordCursor : tm.keySet()) {
  40             System.out.println("Word \"" + wordCursor + "\" occured " + tm.get(wordCursor) + " times");
  41         }
  42
  43         System.out.println("SortedMap content of words inferior to the word \"milieu\":");
  44         SortedMap<String, Integer> sm = tm.headMap("milieu");
  45         for (String wordCursor : sm.keySet()) {
  46             System.out.println("Word \"" + wordCursor + "\" occured " + sm.get(wordCursor) + " times");
  47         }
  48
  49         System.out.println("Map content of exactly duplicated word inferior to the word \"milieu\":");
  50         Map<String, Integer> m1 = tm.entrySet().stream()
  51             .filter(map -> map.getKey().compareTo("milieu") < 0 && map.getValue() == 2)
  52             .collect(Collectors.toMap(p -> p.getKey(), p -> p.getValue()));
  53         for (String wordCursor : m1.keySet()) {
  54             System.out.println("Word \"" + wordCursor + "\" occured " + m1.get(wordCursor) + " times");
  55         }
  56
  57         System.out.println("Map content of duplicates with occurence between 2 and 5:");
  58         Map<String, Integer> m2 = tm.entrySet().stream()
  59             .filter(map -> map.getValue() >= 2 && map.getValue() <= 5)
  60             .collect(Collectors.toMap(p -> p.getKey(), p -> p.getValue()));
  61         for (String wordCursor : m2.keySet()) {
  62             System.out.println("Word \"" + wordCursor + "\" occured " + m2.get(wordCursor) + " times");
  63         }
  64     }
  65 }