Debugging variable error with Java

Question

I am trying to do this stuff. If a user enters "C:\Windows\system32\foo.txt" then the program will convert it to "C:\\Windows\\system32\\foo.txt". A front slash needs to be added to every other preceding slash. Here's what I have coded till now (only the section relevant):

import javax.swing.*;
public class test {
public static void main(String[] args){
    String path = JOptionPane.showInputDialog(null, "Enter the File path", "Word counter", JOptionPane.INFORMATION_MESSAGE);
    for (int z=0;z<=path.length()-1;z++)
    {
        if (path.charAt(z) == '\\')
        {
            path.charAt(z) = "\\\\";
        }
    }
    System.out.println(path); // For knowing what's going on
}
}

Unfortunately it's not compiling, and I don't have a clue of what to do. Any possible help welcomed. Thank you!

Answer 1

You are trying modify a String. Remember strings are immutable.

you can try something like

path.replace(oldChar, newChar) if you want to replace some chars.

Answer 2

This: path.charAt(z) cannot be on the left side of an assignment statement. Instead concatenate your String or use a StringBuilder.

Or just use String's replace(...) method.