返回语句的Java“'.class'预期”

Question

我正在尝试编写一个简单的 Java 程序来计算从五金店订购的零件的发票金额。通过命令提示符编译它后，我会收到“Invoice.java:17: error: '.class' expected return int invoiceAmount;"

我是否在某处遗漏了标识符？我尝试添加数据类型和新方法来再次实例化和显示 invoiceAmount，但这似乎不起作用。任何建议将不胜感激。提前致谢！

//Invoice for hardware store

import java.util.Scanner;

public class Invoice { 
  public static void setInvoice(String[] args) {

    String partNumber;
    String partDescription;
    double price;
    Scanner amountPurchased = new Scanner(System.in);

  }

  public double getInvoiceAmount(){ 
    return int invoiceAmount;       
  }

  private void setInvoice(int amountPurchased){
    int amountPurchased;

    // get quantity of item from user input 
    System.out.println("Please enter quantity of item purchased: ");
    amountPurchased = amountPurchased.nextInt( );

    // get item price from user input   
    System.out.println("Please enter single unit item price: ");
    Scanner price = new Scanner(System.in);

    //multiplies quantity by price per item
    invoiceAmount = amountPurchased * price;
  }
}

Answer 1

您的代码中有多个错误：

• 没有public static void main(String[] args)方法所以程序无法运行
• 在return 语句之后你应该使用变量名而不是类型+变量名
• 在setInvoice 方法中重新定义变量amountPurchased
• 没有对象和对象的字段，因此您无法将结果保存到其中

Here is few materials to help you with java language and object concepts

希望我能有所帮助。