Counting characters in a file

[jenseits]

I need to read in a file and count each character in it. I tried using a while(input.hasNext) loop but that put me into an endless loop. Should i be parsing the file first? I read the APIs but i didn't find any particular hasNext method

[Xeel]

Ugly and direct, considering the deprecated readLine() method, but it would do it:

import java.io.BufferedInputStream;
import java.io.DataInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.text.DecimalFormat;

public class CharCounter {

    public static void main(String[] args) {

        File file = new File("text.txt");
        FileInputStream fis = null;
        BufferedInputStream bis = null;
        DataInputStream dis = null;
        DecimalFormat f = new DecimalFormat("#0");

        try {
            fis = new FileInputStream(file);
            bis = new BufferedInputStream(fis);
            dis = new DataInputStream(bis);
            double count = 0;

            while (dis.available() != 0) {
                count += dis.readLine().length();
            }
            System.out.println("chars in file: "+f.format(count));
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
} 

[dlorde]

Ugly and direct, considering the deprecated readLine() method

You could do the same thing with a BufferedReader and avoid the deprecated method.

Today, most software exists, not to solve a problem, but to interface with other software...
I. O. Angell

[Xeel]

You could do the same thing with a BufferedReader and avoid the deprecated method.

I know... It was a kinda "do-my-homework-for-me" question, so I just took the first "how to read/write files in java" tutorial google gave me and edited the code.

[keang]

so I just took the first "how to read/write files in java" tutorial google gave me and edited the code.

Well that's got to be one of the worst file reading tutorial examples I've ever seen.

Ignoring the deprecated method (I suppose it may not have been deprecated when the tutorial was written) it still is dreadful.

1. The input stream is never closed so if you cut and pasted this into a long running app you'd never release the file resources this code uses and if the code was called repeatedly you'd eventually run out of resources.

2. Using the available() method to test whether the end of file has been reached is totally wrong. The available() method in the words of the API docs "Returns an estimate of the number of bytes that can be read (or skipped over) from this input stream without blocking by the next caller of a method for this input stream". So returning 0 doesn't mean the end of the file has been reached it just means at an instant in time there was nothing to read.