parseInt Exception errors

[TIMBERings]

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:

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:

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.

[masijade]

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

x,2
1
2,x

so that

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.

[TIMBERings]

What I need to read is this:

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.

[masijade]

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.

[TIMBERings]

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

Thank you for your help though.

[masijade]

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