My program produces cannot find symbol error and I'm not sure where I am going wrong

Question

I'm sure some of you have seen this prompt before. I'm sure there's a simple solution but I'm very new to java and need assistance.

My prompt reads:

Assume that a gallon of paint covers about 350 square feet of wall space. Create an application with a main() method that prompts the user for the length, width, and height of a rectangular room. Pass these three values to a method that does the following:

-Calculates the wall area for a room

-Passes the calculated wall area to another method that calculates and returns the number of gallons of paint needed

-Displays the number of gallons needed

-Computes the price based on a paint price of $32 per gallon, assuming that the painter can buy any fraction of a gallon of paint at the same price as a whole gallon

-Returns the price to the main() method

The main() method displays the final price. For example:

You will need 2.0 gallons

The price to paint the room is $64.0

The error(s) I get:

PaintCalculator.java:15:

error: cannot find symbol

computeGallons(area);

symbol: variable area

location: class PaintCalculator

PaintCalculator.java:16: error: cannot find symbol

computeTotalCost(gallons);

symbol: variable gallons

location: class PaintCalculator

2 errors

Here is the code producing the error:

public class PaintCalculator 
{
    public static void main (String args[]) 
    {
        System.out.println("Please enter the length, width, and height of your rectangular room.");
    Scanner input = new Scanner(System.in);
    System.out.println("Enter length >>");
    double length = input.nextDouble();
    System.out.println("Enter width >>");
    double width = input.nextDouble();
    System.out.println("Enter height >>");
    double height = input.nextDouble();
    computeArea(length, width, height);
    computeGallons(area);
    computeTotalCost(gallons);
    }

    public static double computeArea(double length, double width, double height) 
    {
        double area = (length * height * 2 + height * width * 2);
        return area;
    }
    public static double computeGallons(double area) 
    {
        double gallons = (area/350);
        System.out.println("You will need " + gallons + " gallons");
        return gallons;
    }
    public static double computeTotalCost(double gallons)
    {
        double totalCost = gallons * 32;
        System.out.println("The price to paint the room is $" + totalCost);
        return totalCost;
    }
}

Does this answer your question? [What does a "Cannot find symbol" or "Cannot resolve symbol" error mean?](https://stackoverflow.com/questions/25706216/what-does-a-cannot-find-symbol-or-cannot-resolve-symbol-error-mean) — sorifiend, Oct 20 '21 at 05:18

score 2 · Accepted Answer · answered Oct 20 '21 at 05:16

2

You have to assign return value from method computeArea and computeGallons to area and gallons respectively. try changing following:

computeArea(length, width, height);
computeGallons(area);

to

double area = computeArea(length, width, height);
double gallons = computeGallons(area);

answered Oct 20 '21 at 05:16

Sudhir Ojha

3,247
3
14
24

Nevermind, that was exactly what was needed. Can't thank you enough. I thought since they were already defined in other methods I did not need to define them again. You guys rock! – daiger427 Oct 20 '21 at 05:21

score 1 · Answer 2 · answered Oct 20 '21 at 05:09

1

Look closely at your main method. You used variables area and gallons, both of which aren't defined in that scope (or at all for that matter).

answered Oct 20 '21 at 05:09

dilanx

113
1
7

I thought I defined them both under computeGallons and computeArea respectively. Do I need to move where I used the variables to after the methods? I'm very confused as I'm trying to get the program to print the needed gallons and cost but this prevents it, and when I take out computeGallons(area); and computeTotalCost(gallons); it does nothing but prompt the user for the length width and height and then ends. Do I need to remove the use of those variable there entirely? – daiger427 Oct 20 '21 at 05:18

My program produces cannot find symbol error and I'm not sure where I am going wrong

2 Answers2