chore!: use new class keywords for protocol interfaces

Author: JKRhb

lib/src/binding_coap/coap_client.dart

@@ -81,7 +81,7 @@ coap.PskCredentialsCallback? _createPskCallback(
 }
 
 /// A [ProtocolClient] for the Constrained Application Protocol (CoAP).
-class CoapClient extends ProtocolClient {
+final class CoapClient implements ProtocolClient {
   /// Creates a new [CoapClient] based on an optional [CoapConfig].
   CoapClient([this._coapConfig, this._clientSecurityProvider]);
 

lib/src/binding_coap/coap_client_factory.dart

@@ -11,7 +11,7 @@ import 'coap_client.dart';
 import 'coap_config.dart';
 
 /// A [ProtocolClientFactory] that produces CoAP clients.
-class CoapClientFactory extends ProtocolClientFactory {
+final class CoapClientFactory implements ProtocolClientFactory {
   /// Creates a new [CoapClientFactory] based on an optional [CoapConfig].
   CoapClientFactory([this.coapConfig]);
 

lib/src/binding_coap/coap_server.dart

@@ -10,7 +10,7 @@ import '../scripting_api/exposed_thing.dart';
 import 'coap_config.dart';
 
 /// A [ProtocolServer] for the Constrained Application Protocol (CoAP).
-class CoapServer extends ProtocolServer {
+final class CoapServer implements ProtocolServer {
   /// Creates a new [CoapServer] which can be configured using a [CoapConfig].
   CoapServer([CoapConfig? coapConfig])
       : port = coapConfig?.port ?? 5683,

lib/src/binding_http/http_client.dart

@@ -44,7 +44,7 @@ const _authorizationHeader = 'Authorization';
 /// [RFC 7616]: https://datatracker.ietf.org/doc/html/rfc7616
 /// [RFC 6750]: https://datatracker.ietf.org/doc/html/rfc6750
 /// [`ComboSecurityScheme`]: https://w3c.github.io/wot-thing-description/#combosecurityscheme
-class HttpClient extends ProtocolClient {
+final class HttpClient implements ProtocolClient {
   /// Creates a new [HttpClient].
   HttpClient(this._clientSecurityProvider);
 

lib/src/binding_http/http_client_factory.dart

@@ -11,7 +11,7 @@ import 'http_client.dart';
 import 'http_config.dart';
 
 /// A [ProtocolClientFactory] that produces HTTP and HTTPS clients.
-class HttpClientFactory extends ProtocolClientFactory {
+final class HttpClientFactory implements ProtocolClientFactory {
   /// Creates a new [HttpClientFactory] based on an optional [HttpConfig].
   HttpClientFactory([this.httpConfig]);
 

lib/src/binding_http/http_server.dart

@@ -10,7 +10,7 @@ import '../scripting_api/exposed_thing.dart';
 import 'http_config.dart';
 
 /// A [ProtocolServer] for the Hypertext Transfer Protocol (HTTP).
-class HttpServer extends ProtocolServer {
+final class HttpServer implements ProtocolServer {
   /// Create a new [HttpServer] from an optional [HttpConfig].
   HttpServer(HttpConfig? httpConfig)
       // TODO(JKRhb): Check if the scheme should be determined differently.

lib/src/binding_mqtt/mqtt_client.dart

@@ -25,7 +25,7 @@ import 'mqtt_subscription.dart';
 /// [ProtocolClient] for supporting the MQTT protocol.
 ///
 /// Currently, only MQTT version 3.1.1 is supported.
-class MqttClient extends ProtocolClient {
+final class MqttClient implements ProtocolClient {
   /// Constructor.
   MqttClient(
     this._clientSecurityProvider,

lib/src/binding_mqtt/mqtt_client_factory.dart

@@ -13,7 +13,7 @@ import 'mqtt_client.dart';
 import 'mqtt_config.dart';
 
 /// [ProtocolClientFactory] for creating [MqttClient]s.
-class MqttClientFactory extends ProtocolClientFactory {
+final class MqttClientFactory implements ProtocolClientFactory {
   @override
   ProtocolClient createClient([
     ClientSecurityProvider? clientSecurityProvider,

lib/src/core/credentials/credentials.dart

@@ -5,4 +5,4 @@
 // SPDX-License-Identifier: BSD-3-Clause
 
 /// Base class used for defining credentials for Thing Interactions.
-base class Credentials {}
+abstract base class Credentials {}

lib/src/core/protocol_interfaces/protocol_client.dart

@@ -9,7 +9,7 @@ import '../../scripting_api/subscription.dart';
 import '../content.dart';
 
 /// Base class for a Protocol Client.
-abstract class ProtocolClient {
+abstract interface class ProtocolClient {
   /// Starts this [ProtocolClient].
   Future<void> start();