private void injectCustomHeaders(HttpURLConnection connection, String url) {
        Map<String, String> extraHeaders = headerInjector.addHeaders(url);
        for (Map.Entry<String, String> header : extraHeaders.entrySet()) {
            connection.setRequestProperty(header.getKey(), header.getValue());
        }
    }
{@link Source} that uses http resource as source for {@link ProxyCache}.
VideoCache/src/main/java/com/yc/videocache/HttpUrlSource.java