Main.java

package com.company;
import java.util.Scanner;

public class Main {

    public static flat_geometric_shape figure1 = new flat_geometric_shape();
    public static flat_geometric_shape figure2;
    public static String nameFigure;
    //public static Square Sq;
    //public static Rectangle Rect;
    public static boolean t = true;

    public static void main(String[] args)
    {
    // write your code here
        /*figure1.setNameFigure("Figure1");
        System.out.println("Объект" + figure1.getNameFigure() + "\nПлощадь = " + figure1.getS() + "\nПериметр = " + figure1.getP());

        try
        {
            figure1.setNameFigure("");
        }
        catch (IllegalArgumentException e)
        {
            System.out.println(e);
        } */

        String s;
        while(t)
        {
            Processing_Base_class();
            if(figure2 != null)
            {
                switch(s = figure2.getNameFigure())
                {
                    case "Square":
                        //Processing_Square_class();
                        break;
                    case "Rectangle":
                        //Processing_Rectangle_class();
                        break;
                    case "Quit":
                        t = false;
                        break;
                }
            }
            else System.out.println("Объект не создан");

        }
    }

    public static void Processing_Base_class()
    {
        System.out.println("Введите название фигуры : Square или Rectangle или Quit");
        Scanner newin = new Scanner(System.in);
        nameFigure = new String(newin.nextLine());
        try {
            figure2 = new flat_geometric_shape(nameFigure);
        }
        catch(IllegalArgumentException e) {
            System.out.println(e);
        }
    }

    public static void Processing_Square_class()
    {
        System.out.println("Введите длину стороны квадрата");
        Scanner newin = new Scanner(System.in);
        double length = newin.nextDouble();
        try {
            Square Sq = new Square(length, nameFigure);
            Sq.P();
            Sq.S();
            System.out.println(Sq.getNameFigure() + "\nПлощадь = " + Sq.getS() + "\nПериметр = " + Sq.getP());
        }
        catch(IllegalArgumentException e) {
            System.out.println(e);
        }
    }
}

//https://pastebin.com/4QKRQvHL
//https://pastebin.com/S8Vg1imN