Program for counting no. of Chars, Words and Lines in a file

import java.lang.*;
import java.io.*;
import java.util.*;
class WordCount
{
public static void main(String arg[]) throws Exception
{
int char_count=0;
int word_count=0;
int line_count=0;
String s;
StringTokenizer st;
BufferedReader buf=new BufferedReader(new InputStreamReader(System.in));
System.out.print("Enter filename : ");
s=buf.readLine();
buf=new BufferedReader(new FileReader(s));
while((s=buf.readLine())!=null)
{
line_count++;
st=new StringTokenizer(s," ,;:.");
while(st.hasMoreTokens())
{
word_count++;
s=st.nextToken();
char_count+=s.length();
}
}
System.out.println("Character Count : "+char_count);
System.out.println("Word Count : "+word_count);
System.out.println("Line Count : "+line_count);
buf.close();
}
}