Repetition

Main.java

package fr.nargit.repetition;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class Main {

  public static void main(String[] args) {
    BufferedReader in;
    String text;
    String result;
    Map<String, Integer> counts = new HashMap<>();
    try {
      in = new BufferedReader(new FileReader(new File(args[0])));
      text = in.readLine();
      //text = "If you rererererepeat a lieieieieieie often enough, it becomes politics.";
      final String[] split = text.split(" ");
      String token;
      for (int j = 0; j < split.length; j++) {
        String word = split[j];
        for (int i = 2; i < word.length(); i++) {
          for (int k = 0; k < word.length() - i; k++) {
            token = word.substring(k, k + i);

            if (token.length() != token.chars().distinct().count()) {
              break;
            }

            Matcher matcher = Pattern.compile(token).matcher(text);
            int count = 0;
            String aggregatedToken = token;
            while (matcher.find()) {
              count++;
              aggregatedToken += token;
              matcher = Pattern.compile(aggregatedToken).matcher(text);
            }
            final String key = aggregatedToken.substring(0, count * token.length());
            if (count > 1 && !counts.containsKey(key) ||
                counts.containsKey(key) && counts.get(key) < count) {
              counts.put(key, count);
            }
          }
        }
      }
    } catch (Exception e) {
      e.printStackTrace();
    }
    result = counts.entrySet().stream().max((o1, o2) -> {
      if (o1.getKey().length() > o2.getKey().length()) {
        return 1;
      } else {
        return -1;
      }
    }).get().getKey();
    System.out.println(result);
  }
}