How to make the Java.awt.Robot type unicode characters? (Is it possible?)

We have a user provided string that may contain unicode characters, and we want the robot to type that string.

How do you convert a string into keyCodes that the robot will use?
How do you do it so it is also java version independant (1.3 -> 1.6)?

What we have working for "ascii" chars is

//char c = nextChar();
//char c = 'a'; // this works, and so does 'A'
char c = 'á'; // this doesn't, and neither does 'Ă'
Robot robot = new Robot();
KeyStroke key = KeyStroke.getKeyStroke("pressed " + Character.toUpperCase(c) );
if( null != key ) {
  // should only have to worry about case with standard characters
  if (Character.isUpperCase(c))
  {
    robot.keyPress(KeyEvent.VK_SHIFT);
  }

  robot.keyPress(key.getKeyCode());
  robot.keyRelease(key.getKeyCode());

  if (Character.isUpperCase(c))
  {
    robot.keyRelease(KeyEvent.VK_SHIFT);
  }
}

Based on javamonkey79's code I've created the following snippet which should work for all Unicode values...

public static void pressUnicode(Robot r, int key_code)
{
    r.keyPress(KeyEvent.VK_ALT);

    for(int i = 3; i >= 0; --i)
    {
        // extracts a single decade of the key-code and adds
        // an offset to get the required VK_NUMPAD key-code
        int numpad_kc = key_code / (int) (Math.pow(10, i)) % 10 + KeyEvent.VK_NUMPAD0;

        r.keyPress(numpad_kc);
        r.keyRelease(numpad_kc);
    }

    r.keyRelease(KeyEvent.VK_ALT);
}

This automatically goes through each decade of the unicode key-code, maps it to the corresponding VK_NUMPAD equivalent and presses/releases the keys accordingly.


The KeyEvent Class does not have direct mappings for many unicode classes in JRE 1.5. If you are running this on a Windows box what you may have to do is write a custom handler that does something like this:

Robot robot = new Robot();
char curChar = 'Ã';

// -- isUnicode( char ) should be pretty easy to figure out
if ( isUnicode( curChar ) ) {
   // -- this is an example, exact key combinations will vary
   robot.keyPress( KeyEvent.VK_ALT );

   robot.keyPress( KeyEvent.VK_NUMBER_SIGN );
   robot.keyRelease( KeyEvent.VK_NUMBER_SIGN );

   // -- have to apply some logic to know what sequence
   robot.keyPress( KeyEvent.VK_0 );
   robot.keyRelease( KeyEvent.VK_0 );
   robot.keyPress( KeyEvent.VK_1 );
   robot.keyRelease( KeyEvent.VK_1 );
   robot.keyPress( KeyEvent.VK_9 );
   robot.keyRelease( KeyEvent.VK_9 );
   robot.keyPress( KeyEvent.VK_5 );
   robot.keyRelease( KeyEvent.VK_5 );

   robot.keyRelease( KeyEvent.VK_ALT );
}

e.g. Figure out what they key combinations are, and then map them to some sort of Object (maybe a HashMap?) for later lookup and execution.

Hope this helps :)