private static X509TrustManager defaultTrustManager() throws GeneralSecurityException {
        TrustManagerFactory trustManagerFactory = TrustManagerFactory.getInstance(
                TrustManagerFactory.getDefaultAlgorithm());
        trustManagerFactory.init((KeyStore) null);
        TrustManager[] trustManagers = trustManagerFactory.getTrustManagers();
        if (trustManagers.length != 1 || !(trustManagers[0] instanceof X509TrustManager)) {
            throw new IllegalStateException("Unexpected default trust managers:"
                    + Arrays.toString(trustManagers));
        }
        return (X509TrustManager) trustManagers[0];

    }
Returns a trust manager that trusts the VM's default certificate authorities.
ache/src/main/java/achecrawler/crawler/async/fetcher/OkHttpFetcher.java