New to Java

I have been playing around with an auto updating client for a project I am working on.

I have been able to get the client to update fine and save a copy of the new client into where ever the original was run from using the below code:

File file;
CodeSource src = HemClientMain.class.getProtectionDomain().getCodeSource();
if (src != null) 
{
	try
	{
		URL url = new URL(src.getLocation(), "UpdatedClient.jar");
		System.out.println("Writing to: " + url.getPath());
				
		file = new File(url.getPath());
		if (!file.exists())
		{
			file.createNewFile();
		}
				
		FileOutputStream fos = new FileOutputStream(file);
		BufferedOutputStream bos = new BufferedOutputStream(fos);

However when I tried running this on my laptop I get a file not found error:

Writing to: /C:/Documents%20and%20Settings/Rob/Desktop/UpdatedClient.jar
java.io.IOException: The system cannot find the path specified
        at java.io.WinNTFileSystem.createFileExclusively(Native Method)
        at java.io.File.createNewFile(File.java:883)
        at Client.ClientGameThread.saveNewClient(ClientGameThread.java:584)
        at Client.ClientGameThread.gameClientFinishedUpdating(ClientGameThread.java:564)
        at Client.ClientListenThread.dealWithPacket(ClientListenThread.java:96)
        at Client.ClientListenThread.listen(ClientListenThread.java:74)
        at Client.ClientListenThread.run(ClientListenThread.java:38)

It's clearly something to do with the location and the path not being correct, as if I move the client to say .. c:/ and run it it updates and saves fine.

Is it something to do with the spaces in between document and settings? And if so how do I stop this from happening? Is there another way I can accurately find the path to the current jar file and save a copy there?

I used to do it via this code:

String fileLocation = System.getProperty("java.class.path");	

However I now have more than one thing in my classpath and this doesn't produce one path but a combination of them all ... which is not really what I want. There must be a nice way to do this!

Any help / suggestions appreciated. Any further questions I will attempt to answer my best :)