Constant Change

Take the input from a file and write the transpose back into it. For example:
If the file consisted
"abc"
"def"
"xyz"
you need to write a program which writes the transpose i.e.
"adx"
"bey"
"cfz"
into the file.

Solution

package com.java;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

public class TransposeFile

{
    public static void main(String args[])
        throws IOException
    {
        List<String> list = new ArrayList<String>();
        FileReader fr = new FileReader(new File("D:\\ip.txt"));
        BufferedReader br = new BufferedReader(fr);
        String s = null;
        while ((s = br.readLine()) != null)
        {
            int j = 0;
            char[] chararry = s.toCharArray();
            while (j < chararry.length)
            {
                String temps = "";
                if (list.size() == 0)
                {
                    temps = "" + chararry[j];
                }
                else
                {
                    if (j < list.size())
                    {
                        temps = list.get(j) + "" + chararry[j];
                        list.remove(j);
                    }
                    else
                    {
                        temps = "" + chararry[j];
                    }
                }
                list.add(j, temps);
                j++;
            }
        }
        FileWriter fw = new FileWriter(new File("D:\\op.txt"));
        BufferedWriter bw = new BufferedWriter(fw);
        for (String st : list)
        {
            bw.write(st);
            bw.flush();
            bw.newLine();
        }
        bw.close();
        fw.close();

    }

}