Make all implementations final

src/Middleware/CallableMiddlewareDecorator.php

@@ -32,7 +32,7 @@
  * Neither the arguments nor the return value need be typehinted; however, if
  * the signature is incompatible, a PHP Error will likely be thrown.
  */
-class CallableMiddlewareDecorator implements MiddlewareInterface
+final class CallableMiddlewareDecorator implements MiddlewareInterface
 {
     /**
      * @var callable

src/Middleware/DoublePassMiddlewareDecorator.php

@@ -34,7 +34,7 @@
  * Neither the arguments nor the return value need be typehinted; however, if
  * the signature is incompatible, a PHP Error will likely be thrown.
  */
-class DoublePassMiddlewareDecorator implements MiddlewareInterface
+final class DoublePassMiddlewareDecorator implements MiddlewareInterface
 {
     /**
      * @var callable

src/Middleware/HostMiddlewareDecorator.php

@@ -14,7 +14,7 @@
 use Psr\Http\Server\MiddlewareInterface;
 use Psr\Http\Server\RequestHandlerInterface;
 
-class HostMiddlewareDecorator implements MiddlewareInterface
+final class HostMiddlewareDecorator implements MiddlewareInterface
 {
     /** @var MiddlewareInterface */
     private $middleware;

src/Middleware/NotFoundHandler.php

@@ -15,7 +15,7 @@
 use Psr\Http\Server\MiddlewareInterface;
 use Psr\Http\Server\RequestHandlerInterface;
 
-class NotFoundHandler implements MiddlewareInterface
+final class NotFoundHandler implements MiddlewareInterface
 {
     /**
      * @var callable

src/Middleware/OriginalMessages.php

@@ -30,7 +30,7 @@
  * - Determining if changes to the response have occurred.
  * - Providing prototypes for factories.
  */
-class OriginalMessages implements MiddlewareInterface
+final class OriginalMessages implements MiddlewareInterface
 {
     public function process(ServerRequestInterface $request, RequestHandlerInterface $handler) : ResponseInterface
     {

src/Middleware/PathMiddlewareDecorator.php

@@ -14,7 +14,7 @@
 use Psr\Http\Server\MiddlewareInterface;
 use Psr\Http\Server\RequestHandlerInterface;
 
-class PathMiddlewareDecorator implements MiddlewareInterface
+final class PathMiddlewareDecorator implements MiddlewareInterface
 {
     /** @var MiddlewareInterface */
     private $middleware;

src/Middleware/RequestHandlerMiddleware.php

@@ -25,7 +25,7 @@
  * they may be piped or routed to. When processed, they delegate handling to the
  * decorated handler, which will return a response.
  */
-class RequestHandlerMiddleware implements MiddlewareInterface, RequestHandlerInterface
+final class RequestHandlerMiddleware implements MiddlewareInterface, RequestHandlerInterface
 {
     /**
      * @var RequestHandlerInterface Decorated handler to invoke.

src/Next.php

@@ -17,7 +17,7 @@
 /**
  * Iterate a queue of middlewares and execute them.
  */
-class Next implements RequestHandlerInterface
+final class Next implements RequestHandlerInterface
 {
     /**
      * @var RequestHandlerInterface