Exception in thread "main" java.util.NoSuchElementException

Question

I'm practice to write java code and i try to fix this but i don't know how to fix it anymore. I'll show you my code.

In my Fortunecookie.java is:

public class FortuneCookie {
    private String subjectList;
    private String objectList;
    private String verbList;
    private int sWord;
    private int oWord;
    private int vWord;
    private Random random = new Random() enter code here;

    public FortuneCookie() {
        subjectList = "I#You#He#She#It#They";
        objectList = "me#you#him#her#it#";
        verbList = "hate#love#deny#find#hear#forgive#hunt#win#teach";
    }

    public String getFortuneMsg() {
        StringTokenizer subSt = new StringTokenizer(subjectList,"#");
        StringTokenizer objSt = new StringTokenizer(objectList,"#");
        StringTokenizer verbSt = new StringTokenizer(verbList,"#");
        sWord = subSt.countTokens();
        oWord = objSt.countTokens();
        vWord = verbSt.countTokens();
        int c1 = random.nextInt(sWord);
        String line1 = " ";
        String line2 = " ";
        String line3 = " ";
        while(subSt.hasMoreTokens()) {
            line1 = subSt.nextToken("#");
            for (int i=0;i<sWord;i++)
                if (i == c1) {
                    break;
                }
                else{
                    line1 = subSt.nextToken("#");
                }
        }
        int c2 = random.nextInt(oWord);
        while(objSt.hasMoreTokens()) {
            line2 = objSt.nextToken("#");
            for (int i=0;i<sWord;i++)
                if (i == c2) {
                    break;
                }
                else{
                    line2 = objSt.nextToken("#");
                }
        }
        int c3 = random.nextInt(vWord);
        while(verbSt.hasMoreTokens()) {
            line3 = verbSt.nextToken("#");
            for (int i=0;i<sWord;i++)
                if (i == c3) {
                    break;
                }
                else{
                    line3 = verbSt.nextToken("#");
                }
        }
        return line1+line2+line3;
    }

    public void setSubjectList(String aSubjectList) {
        subjectList = aSubjectList;
    }

    public void setObjectList(String aObjectList) {
        objectList = aObjectList;
    }

    public void setVerbList(String aVerbList) {
        verbList = aVerbList;
    }

    public void print() {
        StringTokenizer subSt = new StringTokenizer(subjectList,"#");
        StringTokenizer objSt = new StringTokenizer(objectList,"#");
        StringTokenizer verbSt = new StringTokenizer(verbList,"#");
        sWord = subSt.countTokens();
        oWord = objSt.countTokens();
        vWord = verbSt.countTokens();
        System.out.println("Subject List : "+subjectList);
        System.out.println("Object List : "+objectList);
        System.out.println("Verb List : "+verbList);
    }

And in my FortuneCookieTest.java is

public class FortuneCookieTest {
    public static void main(String[] args) {
        FortuneCookie ck = new FortuneCookie();
        System.out.println(ck.getFortuneMsg());
    }
}

And when I compile and run it:

//Exception in thread "main" java.util.NoSuchElementException
        at java.util.StringTokenizer.nextToken(Unknown Source)
        at java.util.StringTokenizer.nextToken(Unknown Source)
        at CS_111_Homework_2.FortuneCookie.getFortuneMsg(FortuneCookie.java:39)
        at CS_111_Homework_2.FortuneCookieTest.main(FortuneCookieTest.java:6)

How can I solve it?

score 0 · Answer 1 · edited May 23 '17 at 11:46

0

In this part of the code, you can call objSt.nextToken("#") twice, and if the first calls gets the last element, on the second call you'll get the NoSuchElementException as no more elements are available.

while (objSt.hasMoreTokens()) {
    line2 = objSt.nextToken("#");
    for (int i = 0; i < sWord; i++)
        if (i == c2) {
            break;
        } else {
            line2 = objSt.nextToken("#");
        }
}

This is a different use case, but has the same problem

edited May 23 '17 at 11:46

Community

1
1

answered Feb 22 '17 at 11:15

djointster

346
3
12

Thanks you for all your answer.I can solve it now.Thanks you again. :) – Parinya Boonaiem Feb 22 '17 at 18:15

Mouad EL Fakir · Answer 2 · 2017-02-22T12:59:02.383

Actually there are several issues with the code, specially with this method getFortuneMsg() :

you are using sWord for all the loops, instead you should use sWord for the first loop oWordfor the second and vWordand for the last.
Also you are calling line1 = subSt.nextToken("#"); before starting the loop so you have consumed one token already, this could produceNoSuchElementException i suggest to change this for (int i=0; i<sWord; i++) to this for (int i=0; i<sWord - 1; i++) to take in consideration the consumed token.
And for this loop while(subSt.hasMoreTokens()) it will be started all over again if not all tokens are consumed (it could be happen when c1 < sWord) .

Note: The code need some refactoring to prevent duplication and use loops wisely.

Edit: I didn't understand exactly what you are trying to achieve but if I were you I would like to change this method getFortuneMsg() to something like this:

 public String getFortuneMsg() {

    StringTokenizer[] tokenizers = {new StringTokenizer(subjectList, "#"), new StringTokenizer(objectList, "#"), new StringTokenizer(verbList, "#")};

    StringBuilder sb = new StringBuilder();
    for (StringTokenizer tokenizer : tokenizers) {

        int rCount = random.nextInt(tokenizer.countTokens());

        for (int i = 0; i < rCount; i++) {
            tokenizer.nextToken();
        }
        sb.append(tokenizer.nextToken());
    }
    return sb.toString();
}

Thanks you for all your answer.I can solve it now.Thanks you again. :) — Parinya Boonaiem, Feb 22 '17 at 18:16

Exception in thread "main" java.util.NoSuchElementException

2 Answers2