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Thread: Returning methods to main() and other methods

  1. #1
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    Default Returning methods to main() and other methods

    This is a simple paint calculator program I built. I am an absolute beginner and I am having problems returning and displaying methods to the main. I keep trying to call the paintFormula() method back to the main but I keep getting errors. Also I am not sure if I am passing the wallArea() methods "calculated wallArea" to the paintFormula(). I keep trying but nothing works.

    The instructions ask me to:

    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.

     
    import java.util.Scanner;
     
    public class PaintCalculator2
    {
    	public static void main(String [] args)
    	{
    	 Scanner keyboard = new Scanner(System.in);
     
             double wallArea;                            
    	 double height; 
    	 double length; 
    	 double width;
             double price;
             double WallArea;
             double paintQuantity;
     
     
             //Prompts user for the dimensions of the room                         
    	 System.out.print("Please enter the height of the room:   ");
    	 height = keyboard.nextDouble();
     
             System.out.print("Please enter the length of the room:   ");
    	 length = keyboard.nextDouble();
     
             System.out.print("Please enter the width of the room:   ");
    	 width = keyboard.nextDouble();
     
             WallAreaMethod(height, length, width);    
             }
     
     
     
                //Calulates the area of the wall in a room
                public static double WallAreaMethod(double height, double length, double width)
                {
                 double wallArea;
                 wallArea = length * height * width * height;
     
                 return wallArea;
                }
     
     
     
                    //Computes the quanity of paint needed
                    public static double paintFormula(double wallAreaMethod, double price, double height, double length,double width)
                    {
     
                      double wallArea;
                      double paintQuantity;
     
                      paintQuantity = wallAreaMethod * 2 / 350;
     
     
                      System.out.println("For a room of  height " + height + "feet, length " + 
    	          length + " feet, and width " + width + " feet you need to purchase "
    	          + paintQuantity + " gallons of paint.");
     
                      System.out.println("The price will be $" + price + ".");
     
                      price = paintQuantity * 32.0;
     
                      return price; 
                     }
     
    }
    Last edited by jonmackey22; September 25th, 2014 at 05:23 AM.


  2. #2
    Senior Member PhHein's Avatar
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    Default Re: Returning methods to main() and other methods

    what errors are you getting? Also you might think of better method names. Also method names start with lower case letters.

  3. The Following User Says Thank You to PhHein For This Useful Post:

    jonmackey22 (September 25th, 2014)

  4. #3
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    Default Re: Returning methods to main() and other methods

    Welcome to the Forum! Thanks for taking the time to learn to post code correctly, and if you haven't already, please read this topic to see other useful info for newcomers.

    Post the entire text of message you're receiving.

  5. The Following User Says Thank You to GregBrannon For This Useful Post:

    jonmackey22 (September 25th, 2014)

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    Default Re: Returning methods to main() and other methods

    I realize there was some errors in my code but I fixed them. Right now, I am trying to return the price from the paintformula ex: price = paintFormula(wallArea,price,height,length,width); or paintFormula(wallArea,price,height,length,width);. When I call the method I keep getting errors like: PaintCalculator2.java:33: error: variable price might not have been initialized.

  7. #5
    Super Moderator Norm's Avatar
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    Default Re: Returning methods to main() and other methods

    variable price might not have been initialized.
    If you give the variable an initial value the compiler won't warn you about the possibility that the variable might not have a value when you use it.
    If you don't understand my answer, don't ignore it, ask a question.

  8. The Following User Says Thank You to Norm For This Useful Post:

    jonmackey22 (September 25th, 2014)

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