public static void register(RegistryConfig config) throws GeneralSecurityException {
    for (KeyTypeEntry entry : config.getEntryList()) {
      registerKeyType(entry);
    }
  }
Tries to register key managers according to the specification in {@code config}.

@throws GeneralSecurityException if cannot register this config with the {@link Registry}. This
    usually happens when either {@code config} contains any {@link KeyTypeEntry} that is
    already registered or the Registry cannot find any {@link
    com.google.crypto.tink.KeyManager} or {@link com.google.crypto.tink.Catalogue} that can
    handle the entry. In both cases the error message should show how to resolve it.
java_src/src/main/java/com/google/crypto/tink/Config.java