File I/O Problem Java

package problem3;

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;

public class File {

    public static void main(String[] args) {
        String[] words = null;
        String s;
        int flag;
        char ch,ch1;
        BufferedReader br = null;
        try {
            br = new BufferedReader(new FileReader("input.txt"));
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }

        try {
            while ((s = br.readLine()) != null) {
                //System.out.println(s);
                words = s.split(" ");
                for (int i = 0; i < words.length; i++) {
                    flag = words[i].length();
                    if (flag >= 7) {
                        ch = words[i].charAt(0);
                        ch1 = words[i].charAt(flag - 1);
                        if (ch == 'a' || ch == 'e' || ch == 'i' || ch == 'o' || ch == 'u') {
                            if (ch1 == 'a' || ch1 == 'e' || ch1 == 'i' || ch1 == 'o' || ch1 == 'u') {
                                System.out.println(words[i]);
                            }
                        }
                    }

                }
            }

        } catch(IOException e) {
            e.printStackTrace();
        }
    }
}