parseInt Exception errors

I'm taking in an adjacent list and turning it into an adjacent matrix. I can run it without trying to turn input into inputInt.

This is what I have, I know it's sloppy but here:

Code:

---

public class scc {
        public static void main(String[] args) {
               
String fileName=args[0];                //input filename from command line
                String newFile=fileName+".scc";                //create new file with .scc extension
                int size=Integer.parseInt(args[1]);        //number of verticies //THIS IS FINE
                               
                int adjMatrix[][] = new int[size][size];
                int i=0;
                String input;
               
                //----Read from file----
                Scanner fromFile=null;
       
                try {          [INDENT][/INDENT]//try and catch
                        fromFile=new Scanner(new File(fileName));
                }
       
                catch (FileNotFoundException e) {
                        System.err.println("Error opening the file " + fileName);
                        System.exit(0);
                }
                fromFile.useDelimiter(",");
                while(fromFile.hasNextLine()) {
                        while(fromFile.hasNext()){
                                input=fromFile.next();
                                int hold=Integer.parseInt(input);  //THIS IS WHERE I GET ISSUES
                                adjMatrix[i][hold-1]=1;
                        }
                        i++;
                }
                fromFile.close();
                i=0;
                //----------------------------------
                System.out.println("\n\n");
                for (i=0;i<50;i++) {
                        for(int j=0;j<50;j++){
                                System.out.print(adjMatrix[i][j]);
                        }
                        System.out.println();
                }
       
       
        }
}

---

However, with inputInt i get the errors:

Code:

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humer015@humer015-Ubuntu:~/CSCI4041/prog2$ java scc graph.txt 8
Exception in thread "main" java.lang.NumberFormatException: For input string: "2
1
2"
        at java.lang.NumberFormatException.forInputString(NumberFormatException.java:48)
        at java.lang.Integer.parseInt(Integer.java:458)
        at java.lang.Integer.parseInt(Integer.java:499)
        at scc.main(scc.java:33)

---

Any help would be great. Thank you.

Well, your delimeter is "," and, you seemingly have a section of the file that goes like this

Code:

---

x,2
1
2,x

---

so that

Code:

---

2
1
2

---

is read in in the "next" call and the newlines are "screwing up" the parseInt call.

One of the many possible problems with scanner. Try using a Reader and String's split instead.

What I need to read is this:

Code:

---

2
1
2,4
3
2
2,5,7
3,6
4,7,8

---

I've never used reader or string splits before, so I'd like to stick with scanner if possible.

When I was getting what seemed to be fairly correct output, I put commas before and after each line. Which would have been wrong anyway, I put them in to test and forgot to take them out.

If reader and string splits are the only way, can you help me find an understandable site?

Thank you.

There is a first time for everything, and since scanner is obviously not working why try and force it. See the Tutorial (namely the second example), and Google.

I actually ended up using the StringTokenizer procedure... It ended up working.

Thank you for your help though.

StringTokenizer is even worse than Scanner, but more power to you.