dangerframe.java

里面包含了多个java的编程示例！而且举出初学者常常遇到的错误！

import java.awt.*;
import javax.swing.*;

public class DangerFrame extends JFrame {
    public DangerFrame () {
        super("Warning!");
        setSize(400, 70);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        Danger gb = new Danger("Core Breach in Sector 12");
        add(gb);
        setVisible(true);
    }

    public static void main(String[] arguments) {
        DangerFrame frame = new DangerFrame();
    }
}