Java String Parsing的扫描程序问题

Question

感觉我在这里遗漏了一些非常基本的东西，但我的大脑现在已经被炒了。目标是用逗号解析字符串，通过一个循环并在下一行之前抛出。很确定它与userInput = scan.nextLine（）;

有关

import java.util.Scanner;

public class ParseStrings
 {
 public static void main(String[] args)
  {
  Scanner scan = new Scanner(System.in);
  String userInput = "";
  boolean finished = false; 

  while (!finished) 
  {
     System.out.print("Enter input string: \n");

     userInput = scan.nextLine();

     if (userInput.equals("q"))
     {
        System.out.println("First word: " + userInput);
        finished = true; 
     } else
     {
        String[] userArray = userInput.split(",");
        System.out.println("First word: " + userArray[0]);
        System.out.println("Second word: " + userArray[1]);
        System.out.println();
     }
  }
  return;
 }
}

投掷：

Exception in thread "main" java.util.NoSuchElementException: No line found
at java.util.Scanner.nextLine(Scanner.java:1540)
at ParseStrings.main(ParseStrings.java:12)

提前谢谢