Java Swing 不加延长

Question

I am trying to make my first 2D game in Java, and I am stuck at the very last thing.
I have already done all the logic in game, and so do I have a class named World which holds all the information about the world, makes turns.
The problem occurs when I am trying to implement some methods to show world in GUI - by that I mean: I have my parent class: World , and then I have child classes WorldGraphic , where i want to show a beautiful world, with images etc, and WorldStrategy where it is mentioned to show only the most important aspects(not so beautiful but much more 'clear' i would say), and I would like them to be swapped in UI.
And i have decided to choose Java Swing library to do it, but I have came across a big problem - I cannot inherit both World and JFrame(which was neccessary to do GUI in my swing guide), Is there any way to omit it?
My best idea so far was to make public function in my world that would output the data to print, but I have doubts about it effectiveness, I would like to keep it private(protected), and do it somehow on inheritance basis, as my GUI will also have some other options(probably I would have to make a lot public methods)

My question is more about how should the structure of my document look like(so the code is probably useless). As i have already mentioned I am fairly new to Java and I am not sure if it is correct to suddenly make every method public just so ONE of my classes(the GUI actually) could use them.

Answer 1

You have several questions in your one question, which is not fully allowed here, but regardless, let me try to approach the main ones

• First of all, regarding the need to extend JFrame: This is absolutely not necessary and in fact, is usually not recommended. Much better is for you to use JFrames (and other GUI component) where needed, but not extend them unless necessary. Extend the component if you are extending its underlying behaviors, in other words if you're overriding a method such as a JPanel's protected void paintComponent(Graphics g) method.
• Should WorldGraphic and WorldStrategy both extend World? I'm not sure that this is needed or desired. It sounds as if you're trying to separate your program's GUI portion, its "view", from its logic, the "model", and if so, both aspects do not need to and probably shouldn't extend from a parent class, but rather should be connected by a controller class.
• Regarding, "As i have already mentioned I am fairly new to Java and I am not sure if it is correct to suddenly make every method public just so ONE of my classes(the GUI actually) could use them." : only make a method public if it is to be called by an outside class.

Of course, for a more detailed and concrete answer, you'll probably want to post your relevant minimal reproducible example code.