Results 1 to 3 of 3
Like Tree1Likes
  • 1 Post By Tolls

Thread: Problem with an exercise in java

  1. #1
    chkontog is offline Member
    Join Date
    Nov 2012
    Rep Power

    Default Problem with an exercise in java

    Hello, i have an exercise in java that, we want to find word frequency in documents.

    e.g.We have 3 documents a1.txt, a2.txt, a3.txt.

    a1 = {aaa, aaa, bbb, kkk, ccc, hhh}
    a2 = {kkk, aaa, hhh, ddd}
    a3 = {mmm, ccc, ccc, hhh}

    So, the df(document frequency) for the distinct words are:

    aaa = 2
    bbb = 1
    ccc = 2
    ddd = 1
    hhh = 3
    mmm = 1
    kkk = 2 etc

    I have an ArrayList of the above class Word that i store various information about distinct words

    Java Code:
    private ArrayList<Word> words = new ArrayList<Word>();
    public static class Word{
            public int lineNum;
            public int index;
            private int df; //document frequency
            public String name;
            public int wordcount;
            private String filename;
            public Word(int lineNum, int index, String name, int wordcount, String filename, int documentfrequency) {
                this.lineNum = lineNum;
                this.index = index;
       = name;
                this.wordcount = wordcount;
                this.filename = filename;
                this.df = df;
            public int getLineNum() {
                return lineNum;
            public int getIndex() {
                return index;
            public String getName() {
                return name;
            //class to sort words by lineNumber
            public static  class CompLineNum implements Comparator<Word> {
                public int compare(Word arg0, Word arg1) {
                    return arg0.lineNum - arg1.lineNum;
            public static class CompName implements Comparator<Word> {
            private int mod = 1;
            public CompName(boolean desc) {
                if (desc) mod =-1;
            public int compare(Word arg0, Word arg1) {
                return mod*;
    so, to find df i read again the documents and i have the above method to find duplicates of words in documents

    Java Code:
        public void findDfOfWord() throws FileNotFoundException, UnsupportedEncodingException, IOException{
            String wordtemp = null;
            String filetemp = null;
            String[] word = null;
            int duplicatewordcount = 0;
            Map<String, Integer> unique = new LinkedHashMap<String, Integer>();
            //scan all files that we choose for the word
            for(int k=0; k<filelist.length; k++){
                    filename = listOfFiles[filelist[k]].getName();
                    FileInputStream fstream = new FileInputStream(folderpath+"/"+filename);           
                    DataInputStream in = new DataInputStream(fstream);         
                    BufferedReader input = new BufferedReader(new InputStreamReader(in,"UTF-8"));
                    String wordd = input.readLine();
                    for(int j=0; j<wordswithoutduplicates.size(); j++){
                        wordtemp = wordswithoutduplicates.get(j).name;
                        filetemp = wordswithoutduplicates.get(j).filename;
                            word = wordd.split("\\s+");
                            [I]if(wordtemp.compareTo(word.toString()) ==0 && filename.compareTo(wordtemp)==0
                                   && duplicatewordcount<1){[/I]
                                if(unique.get(wordtemp) == null)
                                    unique.put(wordtemp, 1);
                                    unique.put(wordtemp, unique.get(wordtemp) + 1);
                                String uniqueString = join(unique.keySet(), ", ");
                                List<Integer> value = new ArrayList<Integer>(unique.values());
                                System.out.println("Output = " + uniqueString);
                                System.out.println("Values = " + value);
                            wordd = input.readLine();
    but at the code in line 26-27, it doesn't find duplicates at the if condition.

    What is the error?
    Last edited by chkontog; 11-18-2012 at 09:24 PM.

  2. #2
    chkontog is offline Member
    Join Date
    Nov 2012
    Rep Power

    Default Re: Problem with an exercise in java


  3. #3
    Tolls is offline Moderator
    Join Date
    Apr 2009
    Rep Power

    Default Re: Problem with an exercise in java

    Use some debugging.
    Put println() statements in there so you can see what it's comparing, because I don't think this:
    Java Code:
    is doing what you think it is.
    WHat do you think the output of 'word.toString()' is going to be?
    Jingoism likes this.
    Please do not ask for code as refusal often offends.

    ** This space for rent **

Similar Threads

  1. Java exercise
    By Mbka in forum New To Java
    Replies: 9
    Last Post: 06-28-2012, 09:58 PM
  2. Java exercise I REALLY need help on
    By velvetymold in forum New To Java
    Replies: 2
    Last Post: 03-27-2011, 04:02 AM
  3. Problem in an exercise
    By Honest989 in forum New To Java
    Replies: 1
    Last Post: 11-10-2010, 10:08 PM
  4. Exercise problem, how was this output achieved?
    By bs3ac in forum New To Java
    Replies: 8
    Last Post: 08-06-2010, 03:38 PM
  5. Exercise for java 3d
    By armiri in forum Java Software
    Replies: 3
    Last Post: 05-14-2010, 12:13 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts