Question

I’m making a program that makes a fractal, and the user is suppose to choose what colors they what the fractal to be. The only problem is that the color variable won’t work outside the “if” statement. Here’s my code: (Problem in public void fractalEngine down by where pen colors are being set. Those verifiedChoice variables are initiated inside an if statement and don’t seem to carry over to the rest of the code.)

import java.awt.*;
import java.util.Scanner;

class anotherClass
{
    World worldObj = new World();
    Turtle m = new Turtle(100, 340, worldObj);
    Scanner in = new Scanner(System.in);

    public void hello()
    {
        System.out.println("This program is a fractal engine");
        System.out.println("A fractal shape is a geometric shape that represents"); 
        System.out.println("the whole shape, no matter what level of scale");
        System.out.println();
        System.out.println("Your fractal picture will have three different colors,");
        System.out.println("Please pick three of the following:");
        System.out.println("RED, GREEN, BLUE, ORANGE, BLACK, YELLOW, MAGENTA, PINK");
        System.out.println("NOTE: Type your choices just like they appear.");
        System.out.println();
    }


    public void fractalEngine(int pxLength, String fractalRule)
    {
        System.out.println("Choice #1 out of 3: ");
        String choice1 = in.nextLine();
        if(choice1.equals("RED") || choice1.equals("GREEN") || choice1.equals("BLUE") || choice1.equals("ORANGE") || choice1.equals("BLACK") || choice1.equals("YELLOW") || choice1.equals("MAGENTA") || choice1.equals("PINK"))
        {
            System.out.println("Your first choice has been set to " + choice1);
            String verifiedChoice1 = choice1;
        }
        else
        {
            System.out.println("That choice is not valid, your first choice will now be red");
            String verifiedChoice1 = "RED";
        }



        System.out.println("Choice #2 out of 3: ");
        String choice2 = in.nextLine();
        if(choice2.equals("RED") || choice2.equals("GREEN") || choice2.equals("BLUE") || choice2.equals("ORANGE") || choice2.equals("BLACK") || choice2.equals("YELLOW") || choice2.equals("MAGENTA") || choice2.equals("PINK"))
        {
        System.out.println("Your second choice has been set to " + choice2);
        String verifiedChoice2 = choice2;
        }
        else
        {
            System.out.println("That choice is not valid, your second choice will now be green");
            String verifiedChoice2 = "GREEN";
        }



        System.out.println("Choice #3 out of 3: ");
        String choice3 = in.nextLine();
        if(choice3.equals("RED") || choice3.equals("GREEN") || choice3.equals("BLUE") || choice3.equals("ORANGE") || choice3.equals("BLACK") || choice3.equals("YELLOW") || choice3.equals("MAGENTA") || choice3.equals("PINK"))
        {
            System.out.println("Your thrid choice has been set to " + choice3);
            String verifiedChoice3 = choice3;
        }
        else
        {
            System.out.println("That choice is not valid, your thrid choice will now be blue");
            String verifiedChoice3 = "BLUE";
        }

        m.setHeading(0);
        String subData = "";   
        m.turn(30);
        for(int n = 0; n < fractalRule.length() ; n=n+1)            
        {
            subData = fractalRule.substring(n, n+1);                 

            if(subData.equalsIgnoreCase("F"))
                m.forward(pxLength);
            else if(subData.equals("+"))
                m.turn(120);
            else if(subData.equals("-"))
                m.turn(300);
            else if(subData.equals("1"))
                m.setPenColor(verifiedChoice1);
            else if(subData.equals("2"))
                m.setPenColor(verifiedChoice2);
            else if(subData.equals("3"))
                m.setPenColor(verifiedChoice3);
            else if(subData.equalsIgnoreCase("Q"))              
                m.hide();

        }
    }
}

public class complexFractal
{

    public static void main(String[] args)
    {
       int lineLength = 15;
       String rule = "1F-F+F-F-F-F+F-F+F-F+F-F-F-F+F-F-F-F+F-F-F-F+F-F+F-F+F-F-F-F+F-F+F-F+F-F-F-F+F-F+F-F+F-F-F-F+F-F-F-F+F-F-F-F+F-F+F-F+F-F-F-F+F-F2+F-F+F-F-F-F+F-F+F-F+F-F-F-F+F-F-F-F+F-F-F-F+F-F+F-F+F-F-F-F+F-F+F-F+F-F-F-F+F-F+F-F+F-F-F-F+F-F-F-F+F-F-F-F+F-F+F-F+F-F-F-F+F-F3+F-F+F-F-F-F+F-F+F-F+F-F-F-F+F-F-F-F+F-F-F-F+F-F+F-F+F-F-F-F+F-F+F-F+F-F-F-F+F-F+F-F+F-F-F-F+F-F-F-F+F-F-F-F+F-F+F-F+F-F-F-F+F-FQ";

       anotherClass ac = new anotherClass();

       ac.hello();
       ac.fractalEngine(lineLength, rule);
    }
}

Answer 1

Inside your public void fractalEngine(int pxLength, String fractalRule) just declare the local variables right after the { symbol:

public void fractalEngine(int pxLength, String fractalRule) {
    String verifiedChoice1  = "";
    String verifiedChoice2  = "";
    String verifiedChoice3  = "";

    //Logic here..

}

These local variables is only visible inside the method block and cannot be visible outside of the method.

Just make sure you remove the String word that you mentioned inside your if statement and it can be used locally inside your method.