File name formatting program

dubya · 11-22-2004, 11:47 AM

Hey everyone,
This may seem a little trivial, but here it goes anyway: I'm trying to write a java program that will take in file names as Strings and then look through the name for whitespace and replace it with a _. Reading the file names in is no problem, however then fundamental aspect of changing the characters doesn't work. Here is the code for that part:

Code:

		for (int i = 0; i < args.length; i++)
		{
			System.out.println("Before: " + args[i]);
			args[i] = args[i].replace(' ', '_');
			System.out.println("After : " + args[i]);
		}

where args is an array of strings containing the file names. I know this doesn't physically change the file names, I'm just testing to see if it will actually do it, which it doesn't. Anyone know why? Thanks.

CroMagnon · 11-22-2004, 06:44 PM

Hmmm... it works for me:

Code:

Q:\java\test>cat wank.java
class wank {
        public static void main( String[] args ) {

                for (int i = 0; i < args.length; i++)
                {
                        System.out.println("Before: " + args[i]);
                        args[i] = args[i].replace(' ', '_');
                        System.out.println("After : " + args[i]);
                }
        }
}

Q:\java\test>javac wank.java

Q:\java\test>java wank "big fat paulie"
Before: big fat paulie
After : big_fat_paulie

Perhaps it has to do with the way you're running it - are you quoting the files that have spaces in them?

dubya · 11-22-2004, 07:01 PM

Thanks a lot!

One more quick question: do you know of a function that will only change the name of a file and not write an entirely new file? Thanks again.

CroMagnon · 11-22-2004, 07:25 PM

I'm not big on java personally, but it looks like the File object has a renameTo() method (see here: http://java.sun.com/j2se/1.3/docs/api/java/io/File.html ).

dubya · 11-22-2004, 08:07 PM

Thanks a lot!