public long tick()
  {
    long tick = _clock.currentTimeMillis();
    long diff = tick - _tick;

    _tick = tick;

    return diff;
  }
public long tick()
  {
    long tick = _clock.currentTimeMillis();
    long diff = tick - _tick;

    _tick = tick;

    return diff;
  }
public long tick ( ) { long tick = _clock . currentTimeMillis ( ) ; long diff = tick - _tick ; _tick = tick ; return diff ; }
Returns the number of milliseconds ellapsed since the last call to
this function.

@return the number of milliseconds since last call
Returns the number of milliseconds ellapsed since the last call to this function .