java - 如何使 NoSuchElementException 不显示并将其替换为我自己的错误消息

Question

所以我应该做的是让这段代码通过文件names.txt(包含大约一千个婴儿名字及其从1900年至今的排名)搜索我输入的名字，并让程序打印出名称和排名。 如果文件中不存在该名称，则应该打印出诸如“名称未找到”之类的内容。 我的问题是，它要么在找到名字之前打印出“名字未找到”大约 2k 次，要么每年打印出“名字未找到”，直到我找到姓氏并且它意识到它不存在。然后它打印出 cpu 生成的错误。 我也不应该让错误只是计算机生成的错误。请帮忙。

import java.util.Scanner;
import java.io.*;

public class BabyNames {
    public static void main(String[] args)
            throws FileNotFoundException {
        Scanner input = new Scanner(System.in);
        Scanner reader = new Scanner(new File("names.txt"));
        String findNameOriginal = " ";
        String findName = " ";
        int space = 0;
        int rank = 0;
        int year = 1900;
        System.out.println("This program graphs the popularity of a name in 11 decades' worth of statistics recorded since the year 1900.");
        System.out.print("Type a name: ");
        String name = input.next();
        System.out.println("\nPopularity ranking of name \"" + name + "\"");

        while (!findName.equalsIgnoreCase(name)) {
            findNameOriginal = reader.nextLine();
            Scanner nameLine = new Scanner(findNameOriginal);
            space = findNameOriginal.indexOf(" ");
            findName = nameLine.next();
            for (year = 1900; year <= 2000; year += 10) {
                rank = nameLine.nextInt();
                if (findName.equalsIgnoreCase(name)) {
                    System.out.println(year + ": " + rank);
                } else {
                    System.out.println("Name not found");

                }

            }
        }
    }
}

(不确定此名称和数据链接是否有效) http://fcps.blackboard.com/@@/3773575E3802F997E96CECF10E46CA25/courses/1/030-1-348-31840002-1314-YR/content/_27024448_1/names.txt

Answer 1

您可以添加一个 boolean 值来跟踪是否找到该名称:

 boolean found=false;
    while ((findNameOriginal = reader.nextLine()) != null)
      {
         Scanner nameLine = new Scanner(findNameOriginal);
         space = findNameOriginal.indexOf(" ");
         findName = nameLine.next();            
         for (year = 1900; year <= 2000; year += 10)
         {
            rank = nameLine.nextInt();        
            if (findName.equalsIgnoreCase(name))
            {
               System.out.println(year + ": " + rank);
               found=true;
            }


         }

      }  
if(!found) System.out.println("Name not found");