Fixes issue 24868 Clean code: fix unlikely argument and remove some

unused variables. ManagedBeanManagerImpl and
JdbcConnPoolAppStatsProvider need specific review.
(Fix checkstyle 'Line has trailing spaces')

appserver/appclient/client/acc/src/main/java/org/glassfish/appclient/client/acc/HTTPInputArchive.java

@@ -122,12 +122,12 @@ public boolean exists() {
         if (exists != null) {
             return exists.booleanValue();
         }
-        
+
         exists = Boolean.FALSE;
         try (InputStream is = archiveURL.openStream()) {
             exists = Boolean.TRUE;
         } catch (IOException e) {
-            // Ignore, exists is false. 
+            // Ignore, exists is false.
         }
         return exists.booleanValue();
     }