Stopping a infinite loop

Question

I'm trying to write to a file by using a while loop. I read from the keyboard and then enter the while loop. I print to the file and then I read from the keyboard again. My problem is when I want to exit the loop by entering nothing I can't. The loop becomes infinite. Please help!!! Here is my code!!
inputline = keyboard.readLine();//read the keyboard
while ( inputline != null ){
DiskOut.println( inputline );
DiskOut.flush();
inputline = keyboard.readLine();//read the keyboard again
}//end while

Answer 1

They're right...look at the following
public static void doIt5() throws IOException
   BufferedReader stdIn = new BufferedReader(
      new InputStreamReader(System.in) );
   System.out.println( "type stuff...Press only ENTER to quit" );
   String input;
   //                1                    2           3
   while ( (input = stdIn.readLine()).equals("") == false )
      // do your thing...
      System.out.println( "echo: " + input );
      1 ---> assigning input from command line
      2 ---> comparing it to an empty string (if you just press ENTER, it
             will be empty)
      3 ---> however, if something was typed, "input" would be non-empty
   // Same thing with a for loop...
   //              1                       2 & 3                1
   for ( input = stdIn.readLine(); !input.equals(""); input = stdIn.readLine() )
      // do your thing...
      System.out.println( "echo: " + input );