Question

I’m being told by Eclipse to change the modifier of my string variable to static. I don’t understand why. I think I’m declaring everything right but I’m not sure.
Here’s my code. The problem is happening on both lines 12 and 13.

import java.awt.*;
import javax.swing.*;
public class MainClass {


    Rectangle dot1 = new Rectangle(1,1), dot2 = new Rectangle(1,1);
    JFrame frame = new JFrame("Pythagorean Theorem");


    public static void main (String[] args){

        frame.setVisible(true);
        frame.setSize(500, 500);

    }


}

Answer 1

You are defining frame as an instance variable, but using it as a static variable. There are two solutions to this:

1) You can change the modifier of frame to static

2) Create an instance of your class, like this:

public static void main (String[] args){
    MainClass mc = new MainClass();
    mc.frame.setVisible(true);
    mc.frame.setSize(500, 500);
}