将文本文件中的唯一单词添加到 ArrayList 的程序 [英] Program that adds unique words from text file to an ArrayList

问题描述

我正在编写一个程序，该程序读取包含多行文本的文本文件并将唯一的单词添加到 ArrayList.然后，我需要对这个 ArrayList 进行排序并打印它.我的输入是:

I am writing a program that reads a text file with multiple lines of text and adds unique words to an ArrayList. Then, I need to sort this ArrayList and print it. My input is:

你好我的
我的名字是

Hello my
my name is
Java.

我最初认为我的问题是一旦扫描器遇到一个已经在 ArrayList 中的单词，它就会停止.但是，在更改我的输入后，我不知道我的问题是什么了.我的输出现在是:

I originally thought my problem was that once the Scanner hit a word that is already in the ArrayList, it stopped. But, after changing my input, I have no idea what my problem is anymore. My output is now:

有2个独特的词
这些话是:
是
我的

There are 2 unique word(s)
These words are:
is
my

我需要我的输出:

有5个独特的词
这些话是:
你好
爪哇
是
我的
姓名

There are 5 unique word(s)
These words are:
Hello
Java
is
my
name

这是我的代码:

import java.util.*;
import java.io.*;
public class Indexer
{
   public static void main(String[] args) throws FileNotFoundException
   {
      Scanner fileScanner = new Scanner(new File("File.txt"));
      fileScanner.useDelimiter("[^A-Za-z0-9]");
      ArrayList<String> words = new ArrayList<String>();
      while (fileScanner.hasNext())
      { 
         if (!words.contains(fileScanner.next()) && (fileScanner.hasNext()))
         {
           words.add(fileScanner.next());
         }
      }
      Collections.sort(words);
      System.out.println("There are " +  words.size() + " unique word(s)");
      System.out.println("These words are:");
      for (Iterator<String> it = words.iterator(); it.hasNext();) 
      {
          String f = it.next();
          System.out.println(f);
      }
      fileScanner.close();
   }
}

我做错了什么?

推荐答案

您重复使用了 next()，超过了它应该使用的次数.在变量中收集 next() 调用的值并使用它.例如

You're using the next() repeatedly, more than it should be used. Collect the value of the next() call in a variable and use that instead. E.g.

while (fileScanner.hasNext())
    {
        String nextWord = fileScanner.next();
        if (!words.contains(nextWord))
        {
            words.add(nextWord);
        }
    }

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