diff --git a/subsystem/src/main/java/org/keycloak/subsystem/extension/CredentialRemoveHandler.java b/subsystem/src/main/java/org/keycloak/subsystem/extension/CredentialRemoveHandler.java
index 9d1d698df8..1cad10bfb0 100644
--- a/subsystem/src/main/java/org/keycloak/subsystem/extension/CredentialRemoveHandler.java
+++ b/subsystem/src/main/java/org/keycloak/subsystem/extension/CredentialRemoveHandler.java
@@ -27,7 +27,7 @@ import org.jboss.dmr.ModelNode;
  *
  * @author Stan Silvert ssilvert@redhat.com (C) 2014 Red Hat Inc.
  */
-public class CredentialRemoveHandler extends AbstractRemoveStepHandler {
+public final class CredentialRemoveHandler extends AbstractRemoveStepHandler {
 
     public static CredentialRemoveHandler INSTANCE = new CredentialRemoveHandler();
 
diff --git a/subsystem/src/main/java/org/keycloak/subsystem/extension/KeycloakAdapterConfigService.java b/subsystem/src/main/java/org/keycloak/subsystem/extension/KeycloakAdapterConfigService.java
index a39fe26be5..ffcce761cd 100644
--- a/subsystem/src/main/java/org/keycloak/subsystem/extension/KeycloakAdapterConfigService.java
+++ b/subsystem/src/main/java/org/keycloak/subsystem/extension/KeycloakAdapterConfigService.java
@@ -38,7 +38,7 @@ import static org.jboss.as.controller.descriptions.ModelDescriptionConstants.ADD
  *
  * @author Stan Silvert ssilvert@redhat.com (C) 2013 Red Hat Inc.
  */
-public class KeycloakAdapterConfigService implements Service<KeycloakAdapterConfigService> {
+public final class KeycloakAdapterConfigService implements Service<KeycloakAdapterConfigService> {
     private static final String CREDENTIALS_JSON_NAME = "credentials";
 
     // Right now this is used as a service, but I'm not sure it really needs to be implemented that way.
diff --git a/subsystem/src/main/java/org/keycloak/subsystem/extension/RealmAddHandler.java b/subsystem/src/main/java/org/keycloak/subsystem/extension/RealmAddHandler.java
index 9705980968..ea080aed3a 100644
--- a/subsystem/src/main/java/org/keycloak/subsystem/extension/RealmAddHandler.java
+++ b/subsystem/src/main/java/org/keycloak/subsystem/extension/RealmAddHandler.java
@@ -34,7 +34,7 @@ import org.jboss.msc.service.ServiceController;
  *
  * @author Stan Silvert ssilvert@redhat.com (C) 2013 Red Hat Inc.
  */
-public class RealmAddHandler extends AbstractAddStepHandler {
+public final class RealmAddHandler extends AbstractAddStepHandler {
 
     public static RealmAddHandler INSTANCE = new RealmAddHandler();
 
diff --git a/subsystem/src/main/java/org/keycloak/subsystem/extension/RealmRemoveHandler.java b/subsystem/src/main/java/org/keycloak/subsystem/extension/RealmRemoveHandler.java
index 98274875dd..a5c5441554 100644
--- a/subsystem/src/main/java/org/keycloak/subsystem/extension/RealmRemoveHandler.java
+++ b/subsystem/src/main/java/org/keycloak/subsystem/extension/RealmRemoveHandler.java
@@ -27,7 +27,7 @@ import org.jboss.dmr.ModelNode;
  *
  * @author Stan Silvert ssilvert@redhat.com (C) 2013 Red Hat Inc.
  */
-public class RealmRemoveHandler extends AbstractRemoveStepHandler {
+public final class RealmRemoveHandler extends AbstractRemoveStepHandler {
 
     public static RealmRemoveHandler INSTANCE = new RealmRemoveHandler();
 
diff --git a/subsystem/src/main/java/org/keycloak/subsystem/extension/SecureDeploymentAddHandler.java b/subsystem/src/main/java/org/keycloak/subsystem/extension/SecureDeploymentAddHandler.java
index 20930b0abf..c5f795c4e1 100644
--- a/subsystem/src/main/java/org/keycloak/subsystem/extension/SecureDeploymentAddHandler.java
+++ b/subsystem/src/main/java/org/keycloak/subsystem/extension/SecureDeploymentAddHandler.java
@@ -34,7 +34,7 @@ import org.jboss.msc.service.ServiceController;
  *
  * @author Stan Silvert ssilvert@redhat.com (C) 2013 Red Hat Inc.
  */
-public class SecureDeploymentAddHandler extends AbstractAddStepHandler {
+public final class SecureDeploymentAddHandler extends AbstractAddStepHandler {
 
     public static SecureDeploymentAddHandler INSTANCE = new SecureDeploymentAddHandler();
 
diff --git a/subsystem/src/main/java/org/keycloak/subsystem/extension/SecureDeploymentRemoveHandler.java b/subsystem/src/main/java/org/keycloak/subsystem/extension/SecureDeploymentRemoveHandler.java
index fedd88f5f4..da0ca7e19d 100644
--- a/subsystem/src/main/java/org/keycloak/subsystem/extension/SecureDeploymentRemoveHandler.java
+++ b/subsystem/src/main/java/org/keycloak/subsystem/extension/SecureDeploymentRemoveHandler.java
@@ -27,7 +27,7 @@ import org.jboss.dmr.ModelNode;
  *
  * @author Stan Silvert ssilvert@redhat.com (C) 2013 Red Hat Inc.
  */
-public class SecureDeploymentRemoveHandler extends AbstractRemoveStepHandler {
+public final class SecureDeploymentRemoveHandler extends AbstractRemoveStepHandler {
 
     public static SecureDeploymentRemoveHandler INSTANCE = new SecureDeploymentRemoveHandler();