import java.io.*;

class iotest2 {
  private static void promptRead(BufferedReader stdin)
				 throws IOException {
    System.out.print("Input a double: ");
    System.out.flush();

    String         inpline;
      if((inpline = stdin.readLine()) != null) {
        double i = Double.valueOf(inpline).doubleValue();
        System.out.println("Double was " + i);
      } else
        System.out.println("Couldn't Read anything");     
  }

  public static void main(String[] argv) {
    BufferedReader stdin = new java.io.BufferedReader
				       (new InputStreamReader(System.in));
    boolean tryagain = true;
    while(tryagain) {
      tryagain = false;
    
      try {
        promptRead(stdin); 
      }
      catch (IOException ioe) {
        System.out.println("Problem in the input stream");
      }
      catch (NumberFormatException nfe) {
        System.out.println("Not a number. Try again.");
        tryagain = true;
      }
    }
  }
}