Text file I/O

[amonita]

Hi, I'm pretty new to Java, and I'm really struggling with getting my code to work. The files compile with no errors, but they are supposed to input/output to text files, and I can't get it to output anything. There are two files in the program, the point of it being to count the frequency of words in a text file, and I just wondered if you could tell me where I need to insert the file names to get the code to work correctly. Thank you

FreqListCreator.java

import java.io.*;
 
public class FreqListCreator {
 
public static void
main(String args[])
throws IOException {
    if(args.length != 1) {
        System.err.println("usage: FreqListCreator filename");
    } else {
        FileTokeniser ft = new FileTokeniser(args[0]);
        FreqList flist = new FreqList();
        while(ft.hasMoreTokens()) {
            flist.add(ft.getNextToken());
        }
        ft.close();
        PrintWriter pw = new PrintWriter(new FileWriter(args[0]+".frq"));
        flist.save(pw);
        pw.close();
    }
}
 

An excerpt from FreqList:

public void
save(PrintWriter pw) {
    Iterator it = storage.keySet().iterator();
    while(it.hasNext()) {
        String word = (String)it.next();
        int freq = getFreq(word);
        pw.println(word+" "+freq);
    }
}
 
 
public static void
main (String args[])
throws IOException {
    FreqList flist = new FreqList();
    BufferedReader br= new BufferedReader(new FileReader(args[0]));
    flist.load(br);
    br.close();
    Iterator it = flist.iterator();
    while(it.hasNext());
          String word = (String) it.next();
          int freq = flist.getFreq(word);
          System.out.println(word+": "+freq);
}
}
 

[r035198x]

What command did you use to run the program? It's expectiong a filename as argument to the main method.

[samido]

Hi, I'm pretty new to Java, and I'm really struggling with getting my code to work. The files compile with no errors, but they are supposed to input/output to text files, and I can't get it to output anything. There are two files in the program, the point of it being to count the frequency of words in a text file, and I just wondered if you could tell me where I need to insert the file names to get the code to work correctly. Thank you

FreqListCreator.java

import java.io.*;
 
public class FreqListCreator {
 
public static void
main(String args[])
throws IOException {
    if(args.length != 1) {
        System.err.println("usage: FreqListCreator filename");
    } else {
        FileTokeniser ft = new FileTokeniser(args[0]);
        FreqList flist = new FreqList();
        while(ft.hasMoreTokens()) {
            flist.add(ft.getNextToken());
        }
        ft.close();
        PrintWriter pw = new PrintWriter(new FileWriter(args[0]+".frq"));
        flist.save(pw);
        pw.close();
    }
}
 

An excerpt from FreqList:

public void
save(PrintWriter pw) {
    Iterator it = storage.keySet().iterator();
    while(it.hasNext()) {
        String word = (String)it.next();
        int freq = getFreq(word);
        pw.println(word+" "+freq);
    }
}
 
 
public static void
main (String args[])
throws IOException {
    FreqList flist = new FreqList();
    BufferedReader br= new BufferedReader(new FileReader(args[0]));
    flist.load(br);
    br.close();
    Iterator it = flist.iterator();
    while(it.hasNext());
          String word = (String) it.next();
          int freq = flist.getFreq(word);
          System.out.println(word+": "+freq);
}
}
 

Sorry man!! but what are this object suppose to do: FileTokeniser ft = new FileTokeniser(args[0]);
FreqList ...

[amonita]

What command did you use to run the program? It's expectiong a filename as argument to the main method.

I built and ran it in NetBeans, I'm not sure where i would put a command line argument?

[r035198x]

I built and ran it in NetBeans, I'm not sure where i would put a command line argument?

After buiding it in Netbeans, it tells you the commands to use for running it from the command prompt.
When you wrote the code you expected that the program would be given a file name as an argument so you have to pass that to main.