Extending the code

I have the following code but i want to add a function which will allow
me to count the number of vowels in the text file. I was wondering if
anyone would be willing to give me some help with this

[CODE]
import java.io.*;
import java.util.*;
public class App {
 //Create BufferedReader class instance
 public static InputStreamReader input = new
InputStreamReader(System.in);
 public static BufferedReader keyboardInput = new BufferedReader
(input);
 public static void main(String[] args) {
  int[] lengths = new int[100]; //Runtime error if the file contains a
word of more than 100 characters
  int longestWord = 0;
        for(int i = 0; i < lengths.length; i++) {
   lengths[i] = 0;
  }
  try {
   System.out.println("Enter the name of the file you wish to read:
");
   String fileName = keyboardInput.readLine();
   FileReader file = new FileReader(new File(fileName));
   BufferedReader myFile = new BufferedReader(file);
   int numTokens = 0;
   int numWords = 0;
   int numChar= 0;
   String line;
   while ((line = myFile.readLine()) != null ) {
    String[] words = line.split(" ");
    numWords = numWords + words.length;
    for (int i = 0; i < words.length;i++) {
     numChar = numChar + words[i].length();
     if(words[i].length() > longestWord) {
      longestWord = words[i].length();
     }
     lengths[words[i].length()] = lengths[words[i].length()] + 1;
    }
   }
   System.out.println("\nThere are " + numWords + " words in the text
file");
   System.out.println("\nThere are " + numChar + " characters in the
text file");
   System.out.println("\nThere length frequency of the words is as
follows:");
   System.out.println("\nLength : Frequency ");
   for(int i = 0; i <= longestWord; i++) { //Print frequencies only up
to the longest word
    System.out.println(i + " :"+lengths[i]);
   }
   myFile.close();
  }
  catch(IOException iO) {
   iO.printStackTrace();
  }
 }
}
[/CODE]