Numerical representation to ASCII art

I'm trying to write a program that will convert a numerical representation of ASCII art to the art itself.

For example,

3 2,+,3,* 5,- 1,+,1,-

Should give:

3

++***

+-

The number that appears at the top of the "art" and numerical representation is the amount of lines that appear in the file.

Here is the code that I have written for this task. The file "origin.txt" contains a numerical representation of ASCII art while the destination folder should get the art itself.

import java.io

import java.util.*; 

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

    throws FileNotFoundException
    {
        File input = new File("origin.txt");
        File output = new File("destination.txt");
        numToImageRep(input,output); 
    }
    public static void numToImageRep(File input, File output)

throws FileNotFoundException
    {
        Scanner read = new Scanner(input);
        PrintStream out = new PrintStream(output);      
       int size =     read.nextInt();                                           
        String symbol; 
        out.println(size);

    for(int i = 0; i < size; i++)                                 
    {
        int x = 0; 
        symbol = read.next();
        while(x < symbol.length())
        {
            char a = symbol.charAt(x);                           
            int c = Character.getNumericValue(a);          
            x = x + 2 ;
            char L = symbol.charAt(x);                    
            for(int j = 0; j < c; j++)
            {
                out.print(L);
            }
            x = x + 2; 
        }
        out.println(); 
    }

}

}

This code seems to work for a numerical format that contains no spaces, but as soon as a space appears in the numerical format, I get a string out of bounds exception.

For example:

2 2,+,* 1,+,-

will convert to art,

but,

2 2, ,5,* 3, ,9,*

Will result in:StringIndexOutOfBoundsException: String index out of range.

I'm not sure why this could be happening. If anybody has any advice for me, I would really appreciate it.

Thank you.