Printing an array

[Mike Johnston]

Hi,

I'm having some trouble with an assignment of mine when it comes to the printing out the sorted array part of the assignment. (Lines 95-98 specifically, although my problem may be coming from another location. This section was just the default code that was provided already.)

I have a feeling it may have something to do with my array I created in trying to print it. How ever I have tried lots of different things like

System.out.println(className(shapes[shapeCounter]) + figureInfo(shapes[shapeCounter]));

but I have a feeling this is totally the wrong direction to go.

Still a beginner to all of this and some help would be awesome.

It compiles and runs with it commented out so I know the other classes are fine.

import java.util.Scanner;
import java.util.Arrays;

/**
 * A program to print information on various Measurable objects
 *
 * @version 1.0
 */
public class FigureInfo
{
    public static final int NUM_SHAPES = 4;
    public static final int FIGS_PER_SHAPE = 3;
    public static final int TOTAL_FIGS = NUM_SHAPES * FIGS_PER_SHAPE;

    public static void main(String[] args)
    {
        Scanner kbd = new Scanner(System.in);

        // introduce yourself
        System.out.print("\n\n"
            + "Sorted Figure Info\n"
            + "------------------\n\n"
            + "This program reads in the sizes of several shapes "
            + "then prints out\ninformation about them "
            + "in order from smallest to largest.\n\n");
        // TODO: delete this note when it's complete!
        System.out.print("NOTE:  currently INCOMPLETE\n\n");

        // declare variables
        double width;   // width of various figures
        double height;  // height of various figures
        int shapeCounter = 0;
        // TODO: make an array for up to TOTAL_FIGS measurable shapes
        Measurable[] shapes = new Measurable[TOTAL_FIGS];

        // get Rectangles (TODO: revise to read FIGS_PER_SHAPE of them)
        for (int i = 0; i < FIGS_PER_SHAPE; i++)
        {
            System.out.print("Enter the width and height of a rectangle: ");
            width = kbd.nextDouble();
            height = kbd.nextDouble();
            kbd.nextLine();
            Rectangle r = new Rectangle(width, height);
        // TODO: revise to add r to the array of measurable shapes
            shapes[shapeCounter] = r;
            shapeCounter++;
        }    

        // get Ovals (TODO: revise to read FIGS_PER_SHAPE of them)
        for (int i = 0; i < FIGS_PER_SHAPE; i++)
        {
        System.out.print("Enter the width and height of an oval: ");
        width = kbd.nextDouble();
        height = kbd.nextDouble();
        kbd.nextLine();
        Oval o = new Oval(width, height);
        // TODO: revise to add o to the array of measurable shapes
            shapes[shapeCounter] = o;
            shapeCounter++;
        } 
        // get Triangles (TODO: revise to read FIGS_PER_SHAPE of them)
        for (int i = 0; i < FIGS_PER_SHAPE; i++)
        {
        System.out.print("Enter the width and height of a triangle: ");
        width = kbd.nextDouble();
        height = kbd.nextDouble();
        kbd.nextLine();
        Triangle t = new Triangle(width, height);
        // TODO: revise to add t to the array of measurable shapes
            shapes[shapeCounter] = t;
            shapeCounter++;
        } 

        // get Circles (TODO: revise to read FIGS_PER_SHAPE of them)
        for (int i = 0; i < FIGS_PER_SHAPE; i++)
        {
        System.out.print("Enter the diameter of a circle: ");
        width = kbd.nextDouble();
        kbd.nextLine();
        Circle c = new Circle(width/2.0);
        // TODO: revise to add c to the array of measurable shapes
            shapes[shapeCounter] = c;
            shapeCounter++;
        }
        
        // TODO: Sort the array
        Arrays.sort(shapes);
        
        // Print out the sorted array (TODO: revise to print array elements)
        System.out.println();
        System.out.println(figureInfoHeader());
        System.out.println(className(r) + figureInfo(r));
        System.out.println(className(o) + figureInfo(o));
        System.out.println(className(t) + figureInfo(t));
        System.out.println(className(c) + figureInfo(c));
        System.out.println();
        
    }

    // Create the header for the shape information table
    public static String figureInfoHeader()
    {
        return String.format("%-10s%10s%10s%20s%20s",
                                "Type", 
                                "Width", "Height", 
                                "Area", "Perimeter")
             + "\n"
             + String.format("%-10s%10s%10s%20s%20s",
                                "----------", 
                                "-----", "------", 
                                "---------", "---------");
    }
    
    // Create the data values for one row of the shape information table
    public static String figureInfo(Measurable m)
    {
        return String.format("%10.1f%10.1f%20.1f%20.1f", 
                                m.getWidth(), m.getHeight(), 
                                m.getArea(), m.getPerimeter());
    }
    
    // get the object's class name as a 10+ character wide String
    // (for the left column of the shape information table)
    public static String className(Object o)
    {
        return String.format("%-10s", o.getClass().getName());
    }
}

[Jeff Verdegan]

Mike Johnston wrote:
I'm having some trouble with an assignment of mine when it comes to the printing out the sorted array part of the assignment

Exactly what kind of trouble? You'll find that people are better able to help you if you TellTheDetails.(⇐click)

[Winston Gutkowski]

Mike Johnston wrote:I have a feeling it may have something to do with my array I created in trying to print it. How ever I have tried lots of different things like

System.out.println(className(shapes[shapeCounter]) + figureInfo(shapes[shapeCounter]));

but I have a feeling this is totally the wrong direction to go.

Still a beginner to all of this and some help would be awesome.

Every class has a toString() method that you are allowed to redefine. I'd suggest you start there.

Implement this method for each of your Shape classes in the form that you want, and then do something like:

for (Shape s : shapes) {
   System.out.println(s);
}

Winston

[Mike Johnston]

Oops sorry.. I thought I had included my error.. Basically I'm getting

FigureInfo.java:95: cannot find symbol
symbol  : variable r
location: class FigureInfo
        System.out.println(className(r) + figureInfo(r));

when I try and compile it (that is with line 95 uncommented and the others commented. I can't seem to find out why I can't find variable"r" (I'm assuming because variable"r" is saved into the array).

[Jeff Verdegan]

Mike Johnston wrote:I can't seem to find out why I can't find variable"r"

Because you haven't defined any such variable in that scope.

Also, one-letter variable names for just about anything other than loop indices are evil.