code: @Deprecated
      protected static TrustManagerFactory buildTrustManagerFactory(
              File certChainFile, TrustManagerFactory trustManagerFactory)
              throws NoSuchAlgorithmException, CertificateException, KeyStoreException, IOException {
          X509Certificate[] x509Certs = toX509Certificates(certChainFile);
  
          return buildTrustManagerFactory(x509Certs, trustManagerFactory);
      }
docs: Build a {@link TrustManagerFactory} from a certificate chain file.
  @param certChainFile The certificate file to build from.
  @param trustManagerFactory The existing {@link TrustManagerFactory} that will be used if not {@code null}.
  @return A {@link TrustManagerFactory} which contains the certificates in {@code certChainFile}