Thread: need help with writing this program

I think if(pCode[orderNum] == "M3487") is the if statement you are talking about.
The reason is pCode[0] - pCode[n] has a value of "null" (String "null" not null pointer).
why? because you never declare the value of each element. you just declared an array of String.

nickans, you've been asked: Please post your code correctly. If uncertain how, please review this link.

[QUOTE=nickans;147057]1 Create a java file in NetBeans, name it Catalog.java.
2 Create one String array to store 3 products for a catalogue
3 Create the appropriate variables to store the product name, product code and product price.
4 At the start of the program display the catalogue for the user by looping through the array and outputting it to the screen with a number listing for each product, as shown above
5 Create an infinite loop to enter orders; to stop the loop the user should enter 0.
6 Keep a running total (accumulator) of all products amount total and sub-total (multiple accumulators)
7 Write a method to calculate the taxes and return a grand total
8 Write another method to print out the order as listed above

hadda look like this

Our catalogue [Product Codes in brackets]:

(1) Condensed Milk [M3487], $9.50 per can.
(2) Distilled Water [W3876], $3.00 a bottle.
(3) Pack Rice [R9983], $12.75 for 5lbs.
Buy something!

Enter Order Number (0 to stop): M3487
Enter Quantity: 2
Enter Order Number (0 to stop): W3876
Enter Quantity: 3
Enter Order Number (0 to stop): R9983
Enter Quantity: 3
Enter Order Number (0 to stop): 0

--- Update ---

this is the code i have so far

its not entering the if statement...can anyone help??

package catalog;
 
import java.util.*;
 
public class Catalog {
 
   static String products[] = new String[3];
   static int answer;
 
    public static void main(String[] args) {
 
             System.out.println("------------------");
             System.out.println("Shopping Catalog");
             System.out.println("------------------");
 
              String[] pCode = new String[3];
              float pPrice[] = new float[3];
              int orderNum = 0;
              int quantity=0;
 
             Scanner s = new Scanner(System.in);
             System.out.println("------------------------------------------");
                System.out.println("condensed milk [M3487], $9.50 per can.");
                    System.out.println("");
                System.out.println("Distilled Water [W3876], $3.00 a bottle.");
                    System.out.println("");
                System.out.println("Pack Rice [R9983], $12.75 for 5lbs.");
             System.out.println("------------------------------------------");
 
 
 
 
                do{
 
                         System.out.println("Please enter order number (0 to stop)");
                                    pCode[orderNum] = s.nextLine();
 
                                            if(pCode[orderNum] == "M3487"){
                                                System.out.println("condensed milk $9.50");
                                                    System.out.println("Enter Quantity");
                                                        quantity = s.nextInt();
                                            }//close if statement
                                            orderNum++;
                     if(answer == 0){
                         break;
                     }//close if
                }while(true);//close while loop
 
    }//close main method
 
}//close class

Wasn't this answer provided in your other thread? Have you lost track, or am I remembering incorrectly? Multiple threads on the same topic end up wasting time and causing confusion so are discouraged.

yes it was, the other thread was solved. i'm confused as to where should i go from here. That's why i posted it here with additional information

so i've gotten this far, but i cant get a grand total. can anyone help with it??

 
package catalog;
 
 
import java.util.*;
public class Catalog1 {
    private static final String[] products = new String[3];
   private static float total=0.0f; 
   private static final float tax = 15/100;
   private static final float[] subTotal = new float[3];
   private static final float[] itemTotal = new float[3];
   private static final double[]pPrice = new double[3];
   private static String []pCode = new String[10];
    public static void main(String[] args) {
            products[0] = "Condensed Milk"; 
             products[1] = "Distilled Water";
             products[2] = "Packed rice";
             pPrice[0] = (9.50);
             pPrice[1] = (3.00);
             pPrice[2] = (12.75);
            int quantity = 0;
            int orderNum = 0;
         Scanner s = new Scanner(System.in);  
 
 
 
             do{ 
                    System.out.println("------------------------------------------");
                    System.out.println("condensed Milk[M3487], $9.50 per can.");
                    System.out.println("");
                    System.out.println("Distilled Water [W3876], $3.00 a bottle.");
                    System.out.println("");
                    System.out.println("packed Rice [R9983], $12.75 for 5lbs.");
                    System.out.println("------------------------------------------");
 
                         System.out.println("Please enter order number (0 to stop)");
                                    pCode[orderNum] = s.nextLine();
 
                                            if(pCode[orderNum].equals("M3487")){
                                                System.out.println("condensed Milk $9.50");
                                                    System.out.println("Enter Quantity");
                                                        quantity = s.nextInt();
                                                           itemTotal[0] = (float) (pPrice[0]*quantity); 
                                     System.out.println(quantity + " condensed Milk @ $9.50 = $" + itemTotal[0]);
 
                                            }else if(pCode[orderNum].equals("W3876")){
                                                 System.out.println("Distilled Water $3.00");
                                                    System.out.println("Enter Quantity");
                                                        quantity = s.nextInt();
                                                            itemTotal[1] = (float) (pPrice[1] * quantity);
                                        System.out.println(quantity +" Distilled Water @ 3.00 = $" + pPrice[1]*quantity);
 
                                            }else if(pCode[orderNum].equals("R9983")){
                                                 System.out.println("packed Rice $12.75");
                                                   System.out.println("Enter Quantity");
                                                       quantity = s.nextInt();
                                                            itemTotal[2] = (float) (pPrice[2] * quantity);
                                         System.out.println(quantity +" Distilled Water @ 3.00 = $" + pPrice[2]*quantity);
 
                                                }else if(pCode[orderNum].equals("0")){
                                                    System.out.println("your total bill is $" + total);
                                                    break;
                                                }//close if statement
                                            orderNum++;
                                            quantity++;
 
 
                }while(true);//close while loop
 
    }
    public static float totalBill() {
 
 
               subTotal[0] = itemTotal[0] * tax;
               total = subTotal[0] + subTotal[1] + subTotal[2] + itemTotal[0] + itemTotal[1] + itemTotal[2];
		return total ; 
 
	}//close bill method
}

What terms are included in the grand total? Once you've determined the answer to that, add those terms together and print them in a statement as the Grand Total = result.

i got it.. problem was that i wasn't calling it in main. but a new problem arrived, after i enter the product code and quantity, the menu appears twice.

So the logic to leave whatever loop the code is in at the time isn't working. Review that logic and fix it.

There's probably a better way than a do/while( true ) loop to present the menu. I'm mostly prejudiced agains while ( true ) loops of any kind, so if it's working for you, ignore me. But there's a better way.

instead of the while(true)..what would u use??

A deterministic approach that applies logic rather than accepting a default result that must be broken out of.

having it in an infinite loop was within the specification of the assignment.