Dictionary Subwords

Problem

Find all possible subwords from a given text.

Note: This code was written to solve one part of problem 13 in Chapter 2 of Mark Stamp's Cryptography and Information (CS265) course (Information Security: Principle and Practice book).

Words to build the Dictionary in the code - http://www-personal.umich.edu/~jlawler/wordlist

Solution

package Cypto;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;

public class Dictionary {

 ArrayList dict = new ArrayList(); //in sorted order

 
 public int countSubWords(String ciphertext) {
  
  return getSubWords(ciphertext).size();
 }
 
 public ArrayList getSubWords(String ciphertext){
  
  ArrayList wordsFound = new ArrayList();
  if(ciphertext.length() == 0) return wordsFound;
  
  ciphertext = ciphertext.toUpperCase();
  
  for(String word: dict){
   if(word.length() > 3 && ciphertext.contains(word)){
    wordsFound.add(word);
   }
  }
  System.out.println(wordsFound);
  return wordsFound;
 }
 
 public boolean isWord(String word){
//  System.out.println(Collections.binarySearch(dict, word.toUpperCase()));
  return Collections.binarySearch(dict, word.toUpperCase()) >= 0 ? true: false;
 }
 
 public Dictionary()
 {
  FileReader fin = null;
  BufferedReader buf = null;
  
  try {
   fin = new FileReader(new File("dictionary.txt"));
   buf = new BufferedReader(fin);
   String input = "";
   while((input = buf.readLine()) !=null){
//    System.out.println(input);
    dict.add(input.toUpperCase());
   }
  } catch (Exception e) {
   e.printStackTrace();
  } finally {
    try {
     if(fin != null) fin.close();
     if(buf != null) buf.close();
    } catch (IOException e) {
     e.printStackTrace();
    }
   
  }
 }
 
 public static void main(String[] args) {
  Dictionary d = new Dictionary();
  System.out.println(d.isWord("been"));
  System.out.println(d.getSubWords("haHbeenwould"));
 }

}