public class Solution {

    public static void main(String[] args) throws IOException {

        BufferedReader reader = new BufferedReader (new InputStreamReader (System.in));
        String file1 = reader.readLine ();
        String file2 = reader.readLine ();
        reader.close ();

        FileInputStream fileInputStream = new FileInputStream (file1);
        FileOutputStream fileOutputStream = new FileOutputStream (file2);

        ArrayList<String> list = new ArrayList<String> ();
        byte[] buffer1 = new byte[fileInputStream.available ()];
        while (fileInputStream.available () > 0) {
           fileInputStream.read (buffer1);
        }

        String temp = new String (buffer1);
        for (String z : temp.split(" ")) {
            float x = Float.parseFloat(z);
            list.add(Math.round(x) + " ");
        }

        for (String h : list) {
            fileOutputStream.write(h.getBytes());
        }

        fileInputStream.close ();
        fileOutputStream.close ();
    }
}

byte[] buffer1 = ...
String temp = new String (buffer1);