NoSuchElementException in - Java

Question

I am trying to read data from a text file and then store it to an array. I assume that there is one word per line. I am getting a NoSuchElementException here:

while (s.hasNextLine()) 
       {
           text = text + s.next() + " ";
       }

This is my code:

public class ReadNote 
{
   public static void main(String[]args) 
   { 


      String text = readString("CountryList.txt");
      System.out.println(text);

      String[] words = readArray("CountryList.txt");

      for (int i = 0; i < words.length; i++) 
      {
         System.out.println(words[i]);
      }
}


  public static String readString(String file) 
  {

       String text = "";

       try{
       Scanner s = new Scanner(new File(file));

       while (s.hasNextLine()) 
       {
           text = text + s.next() + " ";
       }

         } catch(FileNotFoundException e) 
           {
              System.out.println("file not found ");
           }
        return text;
   }


  public static String[] readArray(String file) 
  { 
      int ctr = 0;

       try {
       Scanner s1 = new Scanner(new File(file));

       while (s1.hasNextLine()) 
       {
            ctr = ctr+1;
            s1.next();
       }

       String[] words = new String[ctr];
       Scanner s2 = new Scanner(new File(file));

       for ( int i = 0; i < ctr; i++) 
       {
           words [i] = s2.next();
       }

        return words;

    } catch (FileNotFoundException e) { }
        return null;
 }
}

Here is the message.

    Exception in thread "main" java.util.NoSuchElementException
    at java.util.Scanner.throwFor(Scanner.java:862)
    at java.util.Scanner.next(Scanner.java:1371)
    at ReadNote.readString(ReadNote.java:29)
    at ReadNote.main(ReadNote.java:13)

Possible duplicate of [Java Scanner hasNextLine NoSuchElementException?](http://stackoverflow.com/questions/23604794/java-scanner-hasnextline-nosuchelementexception) — Andy Turner, Jan 29 '16 at 12:03

Idos · Answer 1 · 2016-01-29T12:06:43.237

There are 2 issues with your code as far as I can tell:

You forgot to check hasNextLine() for your second Scanner s2.
When using Scanner you need to check if there is a next line with hasNextLine(), and it will return null at EOF.
You probably want s.nextLine() instead of s.next() in your while loop since you are checking while (s1.hasNextLine()). In general, you have to match your .hasNext... to your .next....

score 0 · Accepted Answer · answered Jan 29 '16 at 12:02

0

For the specific exception you are getting in readString:

while (s.hasNextLine()) {
  text = text + s.next() + " ";
}

You need to either call s.hasNext() in the loop guard, or use s.nextLine() in the body.

answered Jan 29 '16 at 12:02

Andy Turner

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Thanks i just changed it and it worked. Do you have any idea on how i can store it on a combo box? – Lora Gonzales Jan 29 '16 at 12:14
Assuming you mean `JComboBox`, create an instance of it, and then call `addItem`. – Andy Turner Jan 29 '16 at 12:16

score 0 · Answer 3 · edited May 23 '17 at 11:45

As described in this answer.

You have a single extra newline at the end of your file.

hasNextLine() checks to see if there is another linePattern in the buffer. hasNext() checks to see if there is a parseable token in the buffer, as separated by the scanner's delimiter.

You should modify your code to one of the following

while (s.hasNext()) {
    text = text + s.next() + " ";
}

while (s.hasNextLine()) {
    text = text + s.nextLine() + " ";
}

NoSuchElementException in - Java

3 Answers3