Cleaning up:

- Super interface already implements FutureCallback
- No need to override methods to only call super
- Add missing Javadoc tag
- Access static field directly

httpclient5-cache/src/main/java/org/apache/hc/client5/http/impl/cache/AsyncCachingExec.java

@@ -215,7 +215,7 @@ class AsyncCachingExec extends CachingExecBase implements AsyncExecChainHandler
         final CancellableDependency operation = scope.cancellableDependency;
         final HttpClientContext context = scope.clientContext;
         context.setAttribute(HttpClientContext.HTTP_ROUTE, route);
-        context.setAttribute(HttpClientContext.HTTP_REQUEST, request);
+        context.setAttribute(HttpCoreContext.HTTP_REQUEST, request);
 
         final URIAuthority authority = request.getAuthority();
         final String scheme = request.getScheme();

httpclient5-cache/src/main/java/org/apache/hc/client5/http/impl/cache/CachingExec.java

@@ -163,7 +163,7 @@ class CachingExec extends CachingExecBase implements ExecChainHandler {
         final HttpRoute route = scope.route;
         final HttpClientContext context = scope.clientContext;
         context.setAttribute(HttpClientContext.HTTP_ROUTE, scope.route);
-        context.setAttribute(HttpClientContext.HTTP_REQUEST, request);
+        context.setAttribute(HttpCoreContext.HTTP_REQUEST, request);
 
         final URIAuthority authority = request.getAuthority();
         final String scheme = request.getScheme();

httpclient5/src/main/java/org/apache/hc/client5/http/async/methods/IgnoreCompleteExceptonFutureCallback.java

@@ -33,25 +33,10 @@ import org.apache.hc.core5.concurrent.FutureCallback;
  * @since 5.2
  */
 @Deprecated
-public class IgnoreCompleteExceptonFutureCallback<T> extends IgnoreCompleteExceptionFutureCallback<T> implements FutureCallback<T> {
+public class IgnoreCompleteExceptonFutureCallback<T> extends IgnoreCompleteExceptionFutureCallback<T> {
 
     public IgnoreCompleteExceptonFutureCallback(final FutureCallback<T> callback) {
         super(callback);
     }
 
-    @Override
-    public void completed(final T result) {
-        super.completed(result);
-    }
-
-    @Override
-    public void failed(final Exception ex) {
-        super.failed(ex);
-    }
-
-    @Override
-    public void cancelled() {
-       super.cancelled();
-    }
-
 }

httpclient5/src/main/java/org/apache/hc/client5/http/cookie/CookieAttributeHandler.java

@@ -50,6 +50,7 @@ public interface CookieAttributeHandler {
    *
    * @param cookie {@link org.apache.hc.client5.http.cookie.Cookie} to be updated
    * @param value cookie attribute value from the cookie response header
+   * @throws MalformedCookieException if cookie parsing fails for this attribute
    */
   void parse(SetCookie cookie, String value)
           throws MalformedCookieException;