Question

import javax.swing.*;
public class Menu2 {

    protected String[] entreeChoice = {"Rosemary Chicken", "Beef Wellington", "Maine Lobster"};
    private String menu = "";
    private int choice;
    protected char initial[] = new char[entreeChoice.length];


    public String displayMenu(){

       for(int x = 0; x < entreeChoice.length; ++x){
           menu = menu + "\n" + (x+1) + "for" + entreeChoice[x];
           initial[x] = entreeChoice[x].charAt(0);
       }
       throws menuException


       String input = JOptionPane.showInputDialog(null, "Type your selection, then press Enter." + menu);
       choice = Integer.parseInt(input);
       return (entreeChoice[choice - 1]);
    }

}

我在throws menuException上遇到错误。它说：非法启动类型。我差不多完成了代码，只是代码需要修改（照片附加），当我这样做时，我得到了代码放置位置的错误。

photo of code

Answer 1

取决于您想要做什么（抛出异常，或声明您的方法可能抛出该类型的异常）：

要么改变它：

public String displayMenu() throws menuException {

   for(int x = 0; x < entreeChoice.length; ++x){
       menu = menu + "\n" + (x+1) + "for" + entreeChoice[x];
       initial[x] = entreeChoice[x].charAt(0);
   }
   ...
}

或者：

public String displayMenu(){

   for(int x = 0; x < entreeChoice.length; ++x){
       menu = menu + "\n" + (x+1) + "for" + entreeChoice[x];
       initial[x] = entreeChoice[x].charAt(0);
   }
   if (someCondition)
       throw new menuException();
   ...
}

Answer 2

throws menuException应该......

作为方法签名的一部分进行清除并
应该抛出一个实际的Exception类（不是已经存在的实例）......

例如......

public String displayMenu() throws MenuException {

   for(int x = 0; x < entreeChoice.length; ++x){
       menu = menu + "\n" + (x+1) + "for" + entreeChoice[x];
       initial[x] = entreeChoice[x].charAt(0);
   }
   //throws menuException


   String input = JOptionPane.showInputDialog(null, "Type your selection, then press Enter." + menu);
   choice = Integer.parseInt(input);
   return (entreeChoice[choice - 1]);
}

您可能希望阅读Code Conventions for the Java TM Programming Language，这样可以让人们更轻松地阅读您的代码并让您阅读其他代码

修改java代码错误

2 个答案: