This may just be one of the things that I do and find useful, but creating constants for port numbers can be extremely useful for someone who has not read your code and is not using your robot.
Things like
Code:
private static final int DRIVE_LEFT_FRONT = 1;
Jaguar frontLeftDrive = new Jaguar(DRIVE_LEFT_FRONT);
will be a lot easier for others to understand. (And when you want to make a change you can just find your constants and type in a new number)
Also, to find the x axis/y axis value just type joystick.getX() or joystick.getY(). You also do not need to set the value of the joystick to a double before supplying it to the drive() method.
Code:
public static String log(String aMessage){
System.out.println(aMessage);
return aMessage;
}
The above would probably just be better off as a void where you don't have to bother with the return type. You'll just be telling yourself something that you already know.