public static T createConnection()

in log4j-core/src/main/java/org/apache/logging/log4j/core/net/UrlConnectionFactory.java [62:119]
58 lines of code
18 McCabe index (conditional complexity)

    public static <T extends URLConnection> T createConnection(
            final URL url,
            final long lastModifiedMillis,
            final SslConfiguration sslConfiguration,
            final AuthorizationProvider authorizationProvider)
            throws IOException {
        final PropertiesUtil props = PropertiesUtil.getProperties();
        final List<String> allowed = Arrays.asList(Strings.splitList(
                toRootLowerCase(props.getStringProperty(ALLOWED_PROTOCOLS, DEFAULT_ALLOWED_PROTOCOLS))));
        if (allowed.size() == 1 && NO_PROTOCOLS.equals(allowed.get(0))) {
            throw new ProtocolException("No external protocols have been enabled");
        }
        final String protocol = url.getProtocol();
        if (protocol == null) {
            throw new ProtocolException("No protocol was specified on " + url.toString());
        }
        if (!allowed.contains(protocol)) {
            throw new ProtocolException("Protocol " + protocol + " has not been enabled as an allowed protocol");
        }
        URLConnection urlConnection;
        if (url.getProtocol().equals(HTTP) || url.getProtocol().equals(HTTPS)) {
            final HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
            if (authorizationProvider != null) {
                authorizationProvider.addAuthorization(httpURLConnection);
            }
            httpURLConnection.setAllowUserInteraction(false);
            httpURLConnection.setDoOutput(true);
            httpURLConnection.setDoInput(true);
            httpURLConnection.setRequestMethod("GET");
            if (connectTimeoutMillis > 0) {
                httpURLConnection.setConnectTimeout(connectTimeoutMillis);
            }
            if (readTimeoutMillis > 0) {
                httpURLConnection.setReadTimeout(readTimeoutMillis);
            }
            final String[] fileParts = url.getFile().split("\\.");
            final String type = fileParts[fileParts.length - 1].trim();
            final String contentType = isXml(type) ? XML : isJson(type) ? JSON : isProperties(type) ? PROPERTIES : TEXT;
            httpURLConnection.setRequestProperty("Content-Type", contentType);
            if (lastModifiedMillis > 0) {
                httpURLConnection.setIfModifiedSince(lastModifiedMillis);
            }
            if (url.getProtocol().equals(HTTPS) && sslConfiguration != null) {
                ((HttpsURLConnection) httpURLConnection)
                        .setSSLSocketFactory(sslConfiguration.getSslContext().getSocketFactory());
                if (!sslConfiguration.isVerifyHostName()) {
                    ((HttpsURLConnection) httpURLConnection).setHostnameVerifier(LaxHostnameVerifier.INSTANCE);
                }
            }
            urlConnection = httpURLConnection;
        } else if (url.getProtocol().equals(JAR)) {
            urlConnection = url.openConnection();
            urlConnection.setUseCaches(false);
        } else {
            urlConnection = url.openConnection();
        }
        return (T) urlConnection;
    }