Java tutorial
import java.io.*; public class Main { public static void main(String[] args) { try { double d = 1234.5678; RandomAccessFile raf = new RandomAccessFile("c:/test.txt", "rw"); raf.writeDouble(d); raf.seek(0); System.out.println(raf.readDouble()); raf.seek(0); raf.writeDouble(123.4567); raf.seek(0); System.out.println(raf.readDouble()); raf.close(); } catch (IOException ex) { ex.printStackTrace(); } } }