我们如何在Java中提取以元音字母开头且长度为n的所有单词？

Tutorials Point originated from the idea that there exists a class of readers who respond better to 
on-line content and prefer to learn new skills at their own pace from the comforts of their drawing rooms.

import java.io.File;
import java.util.Scanner;
public class WordsStartWithVowel {
   public static String fileToString(String filePath) throws Exception {
      Scanner sc = new Scanner(new File(filePath));
      StringBuffer sb = new StringBuffer();
      String input = new String();
      while (sc.hasNextLine()) {
         input = sc.nextLine();
         sb.append(input);
      }
      return sb.toString();
   }
   public static void main(String args[]) throws Exception {
      String str = fileToString("D:\sample.txt");
      String words[] = str.split(" ");
      for(int i = 0; i < words.length; i++) {
         char ch = words[i].charAt(0);
         if(ch == 'a'|| ch == 'e'|| ch == 'i' ||ch == 'o' ||ch == 'u'||ch == ' ') {
            System.out.println(words[i]);
         }
      }
   }
}

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