java - 从文本文件中将元素单独添加到队列中

Question

我想向队列(链接)添加一个名称，一次从文本文件添加一个名称。如果用户选择选项 1，那么它应该从列表中获取下一个名称。

如果我想添加另一个名称，情况 1 不允许我输入另一个选择。

   int choice = console.nextInt();

   FileReader names = new FileReader("Customer.txt");

   Scanner lookup = new Scanner(names);

   Queue a = new Queue();


   String customerName;
                                      // This loop was just to verify that 
   while(lookup.hasNextLine() ){      // It was actually reading

  customerName = lookup.next(); 
  System.out.println(customerName);

   }


   while(true){

       switch(choice){

    case 1:
            customerName = lookup.next();//For some reason its not giving me
           a.enqueue(customerName); // The choice to enter another number
                   break;           //even though I made the case while(true)

    case 2:

                   break;

    case 3:

                   break;

    case 4:

                   break;

    case 5:

                   break;

    case 6:
               System.out.println(" Exiting......");
        break;


    default:

        continue;


    }

    break;
}

Answer 1

这里的问题是 switch 语句后面有一个break。这会导致您的代码在执行一次 switch 语句后跳出 while 循环。

解决方案是删除中断，如下所示:

while(true){

       switch(choice){

    case 1:
            customerName = lookup.next();//For some reason its not giving me
           a.enqueue(customerName); // The choice to enter another number
                   break;           //even though I made the case while(true)

    case 2:

                   break;

    case 3:

                   break;

    case 4:

                   break;

    case 5:

                   break;

    case 6:
               System.out.println(" Exiting......");
        break;


    default:

        continue;


    }

}