private static String getCanonicalPathFromFileURL()

in netbeansintegration/tags/4.1.4/project_templates/UNOClientAppProject/src/com/sun/star/lib/loader/InstallationFinder.java [469:567]
94 lines of code
24 McCabe index (conditional complexity)

    private static String getCanonicalPathFromFileURL( String oooUrl ) {
        
        String prefix = "file://";
        if (oooUrl.length() < prefix.length()
            || !oooUrl.substring(0, prefix.length()).toLowerCase().equals(
                prefix))
        {
            return null;
        }        
        StringBuffer buf = new StringBuffer(prefix);
        int n = oooUrl.indexOf('/', prefix.length());
        if (n < 0) {
            n = oooUrl.length();
        }
        String host = oooUrl.substring(prefix.length(), n);
        if (host.length() != 0 && !host.toLowerCase().equals("localhost")) {
            return null;
        }
        buf.append(host);
        if (n == oooUrl.length()) {
            buf.append('/');
        } else {
        loop:
            while (n < oooUrl.length()) {
                buf.append('/');
                ++n;
                int n2 = oooUrl.indexOf('/', n);
                if (n2 < 0) {
                    n2 = oooUrl.length();
                }
                while (n < n2) {
                    char c = oooUrl.charAt(n);
                    switch (c) {
                    case '%':
                        byte[] bytes = new byte[(n2 - n) / 3];
                        int len = 0;
                        while (oooUrl.length() - n > 2
                               && oooUrl.charAt(n) == '%')
                        {
                            int d1 = Character.digit(oooUrl.charAt(n + 1), 16);
                            int d2 = Character.digit(oooUrl.charAt(n + 2), 16);
                            if (d1 < 0 || d2 < 0) {
                                break;
                            }
                            int d = 16 * d1 + d2;
                            if (d == '/') {
                                return null;
                            }
                            bytes[len++] = (byte) d;
                            n += 3;
                        }
                        String s;
                        try {
                            s = new String(bytes, 0, len, "UTF-8");
                        } catch (UnsupportedEncodingException e) {
                            return null;
                        }
                        buf.append(s);
                        break;

                    case '#':
                        break loop;

                    default:
                        buf.append(c);
                        ++n;
                        break;
                    }
                }
            }
        }
        URL url;
        try {
            url = new URL(buf.toString());
        } catch (MalformedURLException e) {
            return null;
        }
        String path = url.getFile();
        String fragment = url.getRef();
        if (fragment != null) {
            path += '#' + fragment;
        }
        String ret = null;
        File file = new File( path, SOFFICE );
        try {
            if ( file.isAbsolute() && file.exists() ) {
                try {
                    // resolve symlink
                    ret = file.getCanonicalFile().getParent();
                } catch ( IOException e ) {
                    return null;
                }     
            }
        } catch ( SecurityException e ) {
            return null;
        }
        
        return ret;
    }