code: public static void main(String[] args) throws NoSuchAlgorithmException, InvalidKeyException {
          // The connection string value can be obtained by going to your App Configuration instance in the Azure portal
          // and navigating to "Access Keys" page under the "Settings" section.
          String connectionString = "endpoint={endpoint_value};id={id_value};name={secret_value}";
  
          // Instantiate a client that will be used to call the service.
          ConfigurationAsyncClient client = ConfigurationAsyncClient.builder()
              .credentials(new ConfigurationClientCredentials(connectionString))
              .build();
  
          // Name of the key to add to the configuration service.
          String key = "hello";
  
          // setSetting adds or updates a setting to Azure Application Configuration store. Alternatively, you can call
          // addSetting which only succeeds if the setting does not exist in the store. Or, you can call updateSetting to
          // update a setting that is already present in the store.
          // We subscribe and wait for the service call to complete then print out the contents of our newly added setting.
          // If an error occurs, we print out that error. On completion of the subscription, we delete the setting.
          // .block() exists there so the program does not end before the deletion has completed.
          client.setSetting(key, "world").subscribe(
              result -> {
                  ConfigurationSetting setting = result.value();
                  System.out.println(String.format("Key: %s, Value: %s", setting.key(), setting.value()));
              },
              error -> System.err.println("There was an error adding the setting: " + error.toString()),
              () -> {
                  System.out.println("Completed. Deleting setting...");
                  client.deleteSetting(key).block();
              });
      }
docs: Runs the sample algorithm and demonstrates how to add, get, and delete a configuration setting.
  
  @param args Unused. Arguments to the program.
  @throws NoSuchAlgorithmException when credentials cannot be created because the service cannot resolve the
  HMAC-SHA256 algorithm.
  @throws InvalidKeyException when credentials cannot be created because the connection string is invalid.