參數不能解析為變量？

Question

這是一個相當基本的程序。 當我嘗試打印summaryOutput方法和billOutput方法時，出現錯誤，提示無法將參數解析為變量。

public class PizzaDriver{

    public static void main(String[] args) {
          PizzaOrder order = new PizzaOrder(); 
          PizzaOutput output = new PizzaOutput();
          PizzaInput input = new PizzaInput(); 

          System.out.println(output.menuOutput()); 
          input.readInput(order); 

          System.out.println(summaryOutput1 = output.summaryOutput (numCheese, numPepperoni, numSausage, numVegetarian));
          System.out.println(output.billOutput(String billOutput));
    }
}

公共類PizzaOutput {

public String menuOutput()
{
    String menuOutput1 = "Item        \t Price \nCheese  \t $2.40 \n Sausage \t $3.00 \nPepperoni \t $3.00 \nVegertarian \t $3.00";

    return menuOutput1;

}

public void summaryOutput(int numCheese,int numPepperoni,int numSausage,int numVegetarian)
{
    System.out.println("Cheese: " + numCheese); 

    System.out.println("Pepperoni: " + numPepperoni); 

    System.out.println("Sausage: " + numSausage);

    System.out.println("Vegetarian: " + numVegetarian);


}

public void billOutput(double subTotal, double tax, double carryOut, double totalBill)
{
    System.out.println("Subtotal : " +subTotal);

    System.out.println("Tax : " + tax);

    System.out.println("carryOut : " +carryOut);

    System.out.println("Total Bill: " + totalBill);
}

導入java.util.Scanner;

公共類PizzaInput {掃描儀鍵盤=新的Scanner（System.in）;

public int numCheese, numPepperoni, numSausage, numVegetarian; 



public void readInput(PizzaOrder order)
{
    System.out.print("How many Cheese Pizzas would you like?");
    int numCheese = keyboard.nextInt(); 

    order.setCheese(numCheese); 

    System.out.print("How many Pepperoni pizzas would you like?");
    int numPepeperoni = keyboard.nextInt(); 

    order.setPepperoni(numPepperoni);

    System.out.print("How many Sausage pizzas would you like?");
    int numSausage = keyboard.nextInt(); 

    order.setSausage(numSausage);

    System.out.print("How many Vegetarian pizzas would you like?");
    int numVegetarian = keyboard.nextInt(); 

    order.setVegetarian(numVegetarian);



    }

}

公共類PizzaOrder {私有最終雙倍CHEESE_PRICE = 2.40;

private final double PEPPERONI_PRICE = 3.00;

private final double SAUSAGE_PRICE = 3.00;

private final double VEGETARIAN_PRICE = 3.50; 

private final double SALES_TAX = .025; 

private final double CARRY_OUT = .10; 


public int numCheese, numPepperoni, numSausage, numVegetarian; 


public int getCheese()
{
    return numCheese; 
}

public void setCheese(int numCheese)
{
    this.numCheese=numCheese;
}


public int getPepperoni()
{
    return numPepperoni; 
}

public void setPepperoni(int numPepperoni)
{
    this.numPepperoni=numPepperoni; 
}


public int getSausage()
{
    return numSausage; 
}

public void setSausage(int numSausage)
{
    this.numSausage= numSausage; 
}

public int getVegetarian()
{
    return numVegetarian; 
}

public void setVegetarian(int numVegetarian)
{
    this.numVegetarian = numVegetarian; 
}






public double calculateSubTotal()
{
    double cheeseTotal= numCheese * CHEESE_PRICE; 

    double pepperoniTotal = numPepperoni * PEPPERONI_PRICE; 

    double sausageTotal = numSausage * SAUSAGE_PRICE; 

    double vegetarianTotal = numVegetarian * VEGETARIAN_PRICE; 

    double subTotal = cheeseTotal + pepperoniTotal + sausageTotal + vegetarianTotal; 

    double tax = (subTotal) * SALES_TAX; 

    double totalBill = (tax + subTotal) * CARRY_OUT; 

    return totalBill; 

}

}

Answer 1

當你說跟隨

output.summaryOutput (numCheese, numPepperoni, numSausage, numVegetarian)

它將嘗試在當前方法/類中搜索相同的變量名（ numCheese ， numPepperoni ， numSausage ， numVegetarian ），這些變量名未定義，因此無法確定。

請定義這些內容，否則請正確引用

也沒有為summaryOutput1和@pooja建議定義

System.out.println(output.billOutput(String billOutput));//where is the param billOutput?

應該像

System.out.println(output.billOutput(billOutput));

Answer 2

在調用方法而不是定義方法時，請從以下行中刪除“ String ”。 此外， billOutput已經兩次。 避免名稱沖突。

System.out.println(output.billOutput(String billOutput));

Answer 3

仔細閱讀以下代碼集，並確定在應用程序內部必須執行的更改

public class PizzaOutput {

    private int numCheese;
    private int numPepperoni;
    private int numSausage;
    private int numVegetarian;

    public PizzaOutput(){}

    public PizzaOutput(int numSausage, int numCheese, int numPepperoni, int numVegetarian) {
        this.numSausage = numSausage;
        this.numCheese = numCheese;
        this.numPepperoni = numPepperoni;
        this.numVegetarian = numVegetarian;
    }

    public int getNumCheese() {
        return numCheese;
    }

    public void setNumCheese(int numCheese) {
        this.numCheese = numCheese;
    }

    public int getNumPepperoni() {
        return numPepperoni;
    }

    public void setNumPepperoni(int numPepperoni) {
        this.numPepperoni = numPepperoni;
    }

    public int getNumSausage() {
        return numSausage;
    }

    public void setNumSausage(int numSausage) {
        this.numSausage = numSausage;
    }

    public int getNumVegetarian() {
        return numVegetarian;
    }

    public void setNumVegetarian(int numVegetarian) {
        this.numVegetarian = numVegetarian;
    }

    public String summaryOutput(int numSausage, int numCheese, int numPepperoni, int numVegetarian){
        setNumSausage(numSausage);
        setNumCheese(numCheese);
        setNumPepperoni(numPepperoni);
        setNumVegetarian(numVegetarian);

        return "Sausage : "+ getNumSausage()+ "  Cheese : "+getNumCheese()+ " Pepeeroni : "+ getNumPepperoni()+ " Vegetarian : "+getNumVegetarian();
    }

    public String billOutPut(String bOutput){
        // Enter here your code to get the bill
        return "Bill Output"; // return the bill as a String
    }
}

->注意實例變量的聲明
->您尚未在“ summaryOutput”和“ billOutPut”方法中聲明return語句。 因此，您必須將return語句聲明為單個語句
->根據您的代碼結構，調用這兩個方法足以獲取輸出，而無需在SOP中調用這兩個方法