iam building a training set for spam filtering using java,training set data
is given as words in text files in one folder,but im unable to debug whats going wrong in java collections

 *folder part 1 conatins various text files having name format
 * **spmsg***.txt and ***legit***.txt e.g 11927legit569.txt ,106127spmsgc26
 * inside it it has contents like Subject: 5581 2005 47
 * 1791 80 15184 64 2155 5581 2005 80 21292 10607 47 64
 * 209 22910 132 1672 84 3865 84 1570 84 2005 84 10492 1847 12330 4797 82 13886 2170 47
package naive_bayes;
import java.util.*;
import java.io.*;
 * @author anuran mohanty
 * Indian institute of technology madras
class Naivebayes
{  //dictionary containing words and description are they spam or not?
   private  Map<String, String> Dictionary = new HashMap<String, String>();
   //frequency list of all spam words
   private  Map<String, Integer> spam = new HashMap<String, Integer>();
   //frequency list of all non spam words
   private  Map<String, Integer> legit = new HashMap<String, Integer>();
        // Initialize frequency table from command line
   public  Naivebayes(){
//selecting all the words from spam text files  present in folder part 1
   for (String a : textselector("D:\\study\\ML\\Assignment_1\\Data\\part1","spmsg") ) {
            Integer freq = spam.get(a);
            spam.put(a, (freq == null) ? 1 : freq + 1);
//selecting all the words from non spam text files  present in folder part 1
   for (String a : textselector("D:\\study\\ML\\Assignment_1\\Data\\part1","legit")) {
            Integer freq = legit.get(a);
            legit.put(a, (freq == null) ? 1 : freq + 1);
   //putting the words in dictionary
   for (String value : legit.keySet()) {
   for (String value : spam.keySet()) {

   public ArrayList<String> textselector(String path,String flag)
  ArrayList<String> texts=new ArrayList<String>();
  String files;
  FileReader fr;
  BufferedReader br;
  File folder = new File(path);
  File[] listOfFiles = folder.listFiles();

  for (int i = 0; i < listOfFiles.length; i++)

   if (listOfFiles[i].isFile())
   files = listOfFiles[i].getName();
       if (files.contains(flag))
       { try{ fr = new FileReader(path+"\\"+files);
          br = new BufferedReader(fr);
          Scanner scan = new Scanner(br);
                       texts.add(new String(scan.next().toString()));
        }catch(Exception E){System.out.println("Exception found"+E);}
  return texts;

   public void ShowDictionary()
    { System.out.println("here it is "+Dictionary.values());     }

public class Main {

     * @param args the command line arguments
    public static void main(String[] args) {
        Naivebayes nb=new Naivebayes();

//output coming like "here it is []"
5 Years
Discussion Span
Last Post by anuran

i've got one folder named part 1,it has got many .txt files named as 11927legit569.txt ,106127spmsgc26.txt which as got many words.
so im trying to make two matrices spam and legit which contains frequency of all the words appearing in legit and spam text file.
after that im preparing dictionary which contains all the words in legit and spam matrix with label as spam or legit.
but i don't know why its not working,all the matrices are coming empty


all the matrices are coming empty

They are supposed to be loaded from a list created in textselector, right?
Put lots of print statements between lines 55 and 68 to confirm that it is finding the expected files, and finding the expected words within those files.


I took the code and tried it, it worked fine for me. Though, I got an error when compiled after I just copied and pasted the code because my box is Linux. I need to change the code from

fr = new FileReader(path+"\\"+files);


fr = new FileReader(path+"/"+files);

in order to get it read what I need. Also I changed the read in path (what I used was the same path as the Java class's).

I'm guessing that your "hard-coded" directory that you passed into your textselector() could be wrong. In other words, it may be interpret by Windows. I remember that Windows once confused and changed directory string from "Program Files" to "Progra~1"... Not sure if it is the case...

Edited by Taywin: n/a


thanx sir,its working fine now i dont know i also tried the same thing it's working perfectly.

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