Java Get Full Application Path Cross Platform

AppPath.java

public class AppPath {

    public String getAppPath() {
        URL url;
        String extURL;
        Class anyClass = this.getClass();

        try {
            url = anyClass.getProtectionDomain().getCodeSource().getLocation();

        } catch (SecurityException ex) {
            url = anyClass.getResource(anyClass.getSimpleName() + ".class");
        }

        extURL = url.toExternalForm();

        // prune for various cases
        if (extURL.endsWith(".jar"))
            extURL = extURL.substring(0, extURL.lastIndexOf("/"));
        else {
            // from getResource
            String suffix = "/"+(anyClass.getName()).replace(".", "/")+".class";
            extURL = extURL.replace(suffix, "");
            if (extURL.startsWith("jar:") && extURL.endsWith(".jar!"))
                extURL = extURL.substring(4, extURL.lastIndexOf("/"));
        }

        // convert back to url
        try {
            url = new URL(extURL);
        } catch (MalformedURLException mux) {

        }

        // convert url to File
        File fPath = null;
        try {
            fPath = new File(url.toURI());
        } catch(URISyntaxException ex) {
            fPath = new File(url.getPath());
        }

        // finally, convert File to String
        if(fPath != null) {
            File fDir = fPath.getAbsoluteFile();
            return fDir.toString() + File.separator;
        }

        return null;
    }
    
}