0

クラスを書くのは初めてで、これらすべてのエラーが発生しています：

C:\Users\Eamon\programming\java>javac -Xlint:unchecked Shop1.java
Shop1.java:20: error: cannot find symbol
                if (cart.itemsInCart.products.get(itemIndex).quantity != 0)
                                                            ^
  symbol:   variable quantity
  location: class Object
Shop1.java:21: error: cannot find symbol
                    System.out.println(cart.itemsInCart.products.get(itemIndex).quantity
                                                                               ^
  symbol:   variable quantity
  location: class Object
Shop1.java:22: error: cannot find symbol
                        + " " + cart.itemsInCart.products.get(itemIndex).name
                                                                        ^
  symbol:   variable name
  location: class Object
Shop1.java:23: error: cannot find symbol
                        + " $"+ df.format(cart.itemsInCart.products.get(itemIndex).price)
                                                                                  ^
  symbol:   variable price
  location: class Object
Shop1.java:25: error: cannot find symbol
                        ((cart.itemsInCart.products.get(itemIndex).quantity
                                                                  ^
  symbol:   variable quantity
  location: class Object
Shop1.java:26: error: cannot find symbol
                        * cart.itemsInCart.products.get(itemIndex).price)));
                                                                  ^
  symbol:   variable price
  location: class Object
Shop1.java:35: error: cannot find symbol
                subtotal += cart.itemsInCart.products.get(itemIndex).quantity
                                                                    ^
  symbol:   variable quantity
  location: class Object
Shop1.java:36: error: cannot find symbol
                * cart.itemsInCart.products.get(itemIndex).price;
                                                          ^
  symbol:   variable price
  location: class Object
Shop1.java:126: error: cannot find symbol
                    if (codeInput.equals(this.itemsInCart.products.get(itemIndex).code))
                                                                                 ^
  symbol:   variable code
  location: class Object
Shop1.java:138: error: cannot find symbol
            this.itemsInCart.products.get(itemIndex).quantity = scanner.nextInt();
                                                    ^
  symbol:   variable quantity
  location: class Object
Shop1.java:140: error: cannot find symbol
            if (this.itemsInCart.products.get(itemIndex).quantity > 100)
                                                        ^
  symbol:   variable quantity
  location: class Object
Shop1.java:143: error: cannot find symbol
                    + this.itemsInCart.products.get(itemIndex).quantity
                                                              ^
  symbol:   variable quantity
  location: class Object
Shop1.java:145: error: cannot find symbol
                    + this.itemsInCart.products.get(itemIndex).quantity
                                                              ^
  symbol:   variable quantity
  location: class Object
Shop1.java:147: error: cannot find symbol
                if (scanner.nextInt() != this.itemsInCart.products.get(itemIndex).quantity)
                                                                                 ^
  symbol:   variable quantity
  location: class Object
Shop1.java:148: error: cannot find symbol
                    this.item[itemIndex].quantity = 0;
                        ^
  symbol: variable item
Shop1.java:150: error: cannot find symbol
            if (this.itemsInCart.products.get(itemIndex).quantity < 0)
                                                        ^
  symbol:   variable quantity
  location: class Object
Shop1.java:151: error: cannot find symbol
                this.itemsInCart.products.get(itemIndex).quantity = 0;
                                                        ^
  symbol:   variable quantity
  location: class Object
Shop1.java:50: error: cannot find symbol
        ArrayList products = new Arraylist<Product>(3);
                                 ^
  symbol:   class Arraylist
  location: class Catalogue
Shop1.java:54: warning: [unchecked] unchecked call to add(E) as a member of the raw type ArrayList
            products.add(new Product("Condensed Powdered water", "P3487", 2.50
                        ^
  where E is a type-variable:
    E extends Object declared in class ArrayList
Shop1.java:56: warning: [unchecked] unchecked call to add(E) as a member of the raw type ArrayList
            products.add(new Product("Distilled Moonbeams", "K3876", 3.00
                        ^
  where E is a type-variable:
    E extends Object declared in class ArrayList
Shop1.java:58: warning: [unchecked] unchecked call to add(E) as a member of the raw type ArrayList
            products.add(new Product("Anti-Gravity Pills", "Z9983", 12.75
                        ^
  where E is a type-variable:
    E extends Object declared in class ArrayList
Shop1.java:80: error: Illegal static declaration in inner class Catalogue.Product
            static final Pattern productCodeRegex =
                                 ^
  modifier 'static' is only allowed in constant variable declarations
Shop1.java:83: error: Illegal static declaration in inner class Catalogue.Product
            public static boolean isValidCode(String codeInput)
                                  ^
  modifier 'static' is only allowed in constant variable declarations
Shop1.java:92: error: cannot find symbol
                    + this.products.get(itemIndex).name
                                                  ^
  symbol:   variable name
  location: class Object
Shop1.java:93: error: cannot find symbol
                    + " [" + this.products.get(itemIndex).code + "], $"
                                                         ^
  symbol:   variable code
  location: class Object
Shop1.java:94: error: cannot find symbol
                    + df.format(this.products.get(itemIndex).price) + " "
                                                            ^
  symbol:   variable price
  location: class Object
Shop1.java:95: error: cannot find symbol
                    + this.products.get(itemIndex).rate + ".");
                                                  ^
  symbol:   variable rate
  location: class Object
24 errors
3 warnings

私は戻って作業していますが、これらの変数をうまく見つけることができます。何が与えますか？

import java.util.Scanner;
import java.util.ArrayList;
import java.util.regex.Pattern;
import java.text.DecimalFormat;

public class Shop1
{  
    public static void main(String args[])
    {  
        Cart cart = new Cart(new Catalogue());
        printOrder(cart);
    }

    public static void printOrder(Cart cart)
    {
        DecimalFormat df = new DecimalFormat("0.00");
        System.out.println("Your order:");
        for(int itemIndex = 0; itemIndex < cart.itemsInCart.products.size(); 
            itemIndex++)
            if (cart.itemsInCart.products.get(itemIndex).quantity != 0)
                System.out.println(cart.itemsInCart.products.get(itemIndex).quantity 
                    + " " + cart.itemsInCart.products.get(itemIndex).name 
                    + " $"+ df.format(cart.itemsInCart.products.get(itemIndex).price) 
                    + " = $" + df.format
                    ((cart.itemsInCart.products.get(itemIndex).quantity 
                    * cart.itemsInCart.products.get(itemIndex).price)));

        double subtotal = 0;
        int taxPercent = 20;
        double tax;
        double total;

        for(int itemIndex = 0; itemIndex < cart.itemsInCart.products.size(); 
            itemIndex++)
            subtotal += cart.itemsInCart.products.get(itemIndex).quantity 
            * cart.itemsInCart.products.get(itemIndex).price;
        tax = subtotal * taxPercent / 100;
        total = subtotal + tax;


        System.out.print("Subtotal: $" + df.format(subtotal) 
            + " Tax @ " + taxPercent + "%: $" + df.format(tax) 
            + " Grand Total: $" + df.format(total));
    }  
}

class Catalogue
{
    DecimalFormat df = new DecimalFormat("0.00");
    ArrayList products = new Arraylist<Product>(3);

    public Catalogue()
    {
        products.add(new Product("Condensed Powdered water", "P3487", 2.50
            , "per packet"));
        products.add(new Product("Distilled Moonbeams", "K3876", 3.00
            , "a dozen")); 
        products.add(new Product("Anti-Gravity Pills", "Z9983", 12.75
            , "for 60"));
    }

    class Product
    {
        String name;
        double price;
        String code;
        String rate;
        int quantity;

        public Product(String startName, String startCode, double startPrice
            , String startRate) 
        {
            name = startName;
            code = startCode;
            price = startPrice;
            rate = startRate;
            quantity = 0;
        }

        static final Pattern productCodeRegex = 
            Pattern.compile("^[a-zA-Z][0-9]{4}$"); 

        public static boolean isValidCode(String codeInput)
            {return productCodeRegex.matcher(codeInput).matches();}
    }

    public void printCatalogue()
    {
        System.out.println("Our catalogue (product codes in brackets):");
        for(int itemIndex = 0; itemIndex < this.products.size(); itemIndex++)
            System.out.println("(" + (itemIndex + 1) + ") " 
                + this.products.get(itemIndex).name 
                + " [" + this.products.get(itemIndex).code + "], $"
                + df.format(this.products.get(itemIndex).price) + " " 
                + this.products.get(itemIndex).rate + ".");
        System.out.println("Buy something!");
    }
}

class Cart
{
    Scanner scanner = new Scanner(System.in); //

    int size = 3; //
    String codeInput = "";
    Catalogue itemsInCart;

    public Cart(Catalogue catalogue) 
    {
        itemsInCart = catalogue;
        catalogue.printCatalogue();
        this.selectProducts();
    }

    public void selectProducts()
    {
        while (true)
        {
            System.out.print("Enter product code (0 to check out): ");
            codeInput = scanner.next();
            scanner.nextLine();
            if (codeInput.equals("0")) return;

            for (int itemIndex = 0; itemIndex < this.itemsInCart.products.size(); 
                itemIndex++)
                if (codeInput.equals(this.itemsInCart.products.get(itemIndex).code))
                    this.addToCart(itemIndex);       
            if (Product.isValidCode(codeInput))
                System.out.println("This product code is not on record.");      
            else System.out.println
                ("Sorry, I don't understand! Use product codes only.");
        }         
    }

    public void addToCart(int itemIndex)
    {
        System.out.print("Enter quantity: ");
        this.itemsInCart.products.get(itemIndex).quantity = scanner.nextInt();
        scanner.nextLine();
        if (this.itemsInCart.products.get(itemIndex).quantity > 100)
        {
            System.out.print("That is a large order, " 
                + this.itemsInCart.products.get(itemIndex).quantity 
                + " counts. Is this correct? Enter \"" 
                + this.itemsInCart.products.get(itemIndex).quantity 
                + "\" to confirm, or, enter any other integer to cancel: ");
            if (scanner.nextInt() != this.itemsInCart.products.get(itemIndex).quantity)
                this.item[itemIndex].quantity = 0;
        }
        if (this.itemsInCart.products.get(itemIndex).quantity < 0)
            this.itemsInCart.products.get(itemIndex).quantity = 0;
    }

}
4

2 に答える 2

4

でCatalogue、あなたは必要です

ArrayList<Product> products = new ArrayList<Product>(3);

それ以外の

ArrayList products = new Arraylist<Product>(3);

そうでなければ、コンパイラはどのタイプが返されるかを知りません

cart.itemsInCart.products.get(itemIndex)

コンパイラがここで返される型がであることProductを知っている場合にのみ、コンパイラはあなたがフィールドにアクセスできることを知っていますquantity。いずれかのタイプが返される可能性がある場合は、タイプが.quantity存在しないか、アクセスできない可能性があります。

後で参照できるように、実際に使用しているコードを提供してください。コンパイルすらできないためです。本来Arraylistあるべき場所がありますArrayList（Javaでは大文字と小文字が区別されます）。また、インターフェイスに対してプログラミングすることをお勧めします。そのため、次のように書くことをお勧めします。List<Product> products = new ArrayList<Product>(3);

于 2013-01-03T10:50:38.297 に答える
1

私が見るところ、使用しようとしているシンボルの一部にアクセスできない可能性があります。各クラスを独自のファイルで定義してから、使用するシンボルを作成してpublic、問題が解決するかどうかを確認してください。その後、コードをより適切な方法で構成できます (つまり、直接アクセスする代わりにゲッターとセッターを使用します)。

編集：私の間違い。jlordoの答えは正しいものです。

于 2013-01-03T10:49:13.910 に答える