Add error message

src/main/java/stirling/software/SPDF/controller/api/UserController.java

@@ -222,18 +222,22 @@ public RedirectView saveUser(
 
     @PreAuthorize("hasRole('ROLE_ADMIN')")
     @PostMapping("/admin/deleteUser/{username}")
-    public String deleteUser(@PathVariable String username, Authentication authentication) {
+    public RedirectView deleteUser(@PathVariable String username, Authentication authentication) {
+
+        if (!userService.usernameExists(username)) {
+            return new RedirectView("/addUsers?messageType=deleteUsernameExists");
+        }
 
         // Get the currently authenticated username
         String currentUsername = authentication.getName();
 
         // Check if the provided username matches the current session's username
         if (currentUsername.equals(username)) {
-            throw new IllegalArgumentException("Cannot delete currently logined in user.");
+            return new RedirectView("/addUsers?messageType=deleteCurrentUser");
         }
         invalidateUserSessions(username);
         userService.deleteUser(username);
-        return "redirect:/addUsers";
+        return new RedirectView("/addUsers");
     }
 
     @Autowired private SessionRegistry sessionRegistry;

src/main/resources/messages_ar_AR.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=User not authenticated.
 userNotFoundMessage=User not found.
 incorrectPasswordMessage=Current password is incorrect.
 usernameExistsMessage=New Username already exists.
+deleteCurrentUserMessage=لا يمكن حذف المستخدم الذي قام بتسجيل الدخول حاليًا.
+deleteUsernameExistsMessage=اسم المستخدم غير موجود ولا يمكن حذفه.
 
 
 ###############

src/main/resources/messages_bg_BG.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=Потребителят не е автентикира
 userNotFoundMessage=Потребителят не е намерен
 incorrectPasswordMessage=Текущата парола е неправилна.
 usernameExistsMessage=Новият потребител вече съществува.
+deleteCurrentUserMessage=Не може да се изтрие влезлият в момента потребител.
+deleteUsernameExistsMessage=Потребителското име не съществува и не може да бъде изтрито.
 
 
 ###############

src/main/resources/messages_ca_CA.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=User not authenticated.
 userNotFoundMessage=User not found.
 incorrectPasswordMessage=Current password is incorrect.
 usernameExistsMessage=New Username already exists.
+deleteCurrentUserMessage=No es pot suprimir l'usuari connectat actualment.
+deleteUsernameExistsMessage=El nom d'usuari no existeix i no es pot suprimir.
 
 
 ###############

src/main/resources/messages_de_DE.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=Benutzer nicht authentifiziert.
 userNotFoundMessage=Benutzer nicht gefunden.
 incorrectPasswordMessage=Das Passwort ist falsch.
 usernameExistsMessage=Neuer Benutzername existiert bereits.
+deleteCurrentUserMessage=Der aktuell angemeldete Benutzer kann nicht gelöscht werden.
+deleteUsernameExistsMessage=Der Benutzername existiert nicht und kann nicht gelöscht werden.
 
 
 ###############

src/main/resources/messages_el_GR.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=\u039F \u03C7\u03C1\u03AE\u03C3\u03C4\u03B7\u03C2 \u03B4
 userNotFoundMessage=\u039F \u03C7\u03C1\u03AE\u03C3\u03C4\u03B7\u03C2 \u03B4\u03B5\u03BD \u03B2\u03C1\u03AD\u03B8\u03B7\u03BA\u03B5.
 incorrectPasswordMessage=\u039F \u03C4\u03C1\u03AD\u03C7\u03C9\u03BD \u03BA\u03C9\u03B4\u03B9\u03BA\u03CC\u03C2 \u03C0\u03C1\u03CC\u03C3\u03B2\u03B1\u03C3\u03B7\u03C2 \u03B5\u03AF\u03BD\u03B1\u03B9 \u03BB\u03B1\u03BD\u03B8\u03B1\u03C3\u03BC\u03AD\u03BD\u03BF\u03C2.
 usernameExistsMessage=\u03A4\u03BF \u03BD\u03AD\u03BF \u03CC\u03BD\u03BF\u03BC\u03B1 \u03C7\u03C1\u03AE\u03C3\u03C4\u03B7 \u03C5\u03C0\u03AC\u03C1\u03C7\u03B5\u03B9 \u03AE\u03B4\u03B7.
+deleteCurrentUserMessage=Δεν είναι δυνατή η διαγραφή του τρέχοντος συνδεδεμένου χρήστη.
+deleteUsernameExistsMessage=Το όνομα χρήστη δεν υπάρχει και δεν μπορεί να διαγραφεί.
 
 
 ###############

src/main/resources/messages_en_GB.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=User not authenticated.
 userNotFoundMessage=User not found.
 incorrectPasswordMessage=Current password is incorrect.
 usernameExistsMessage=New Username already exists.
+deleteCurrentUserMessage=Cannot delete currently logged in user.
+deleteUsernameExistsMessage=The username does not exist and cannot be deleted.
 
 
 ###############

src/main/resources/messages_en_US.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=User not authenticated.
 userNotFoundMessage=User not found.
 incorrectPasswordMessage=Current password is incorrect.
 usernameExistsMessage=New Username already exists.
+deleteCurrentUserMessage=Cannot delete currently logged in user.
+deleteUsernameExistsMessage=The username does not exist and cannot be deleted.
 
 
 ###############

src/main/resources/messages_es_ES.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=Usuario no autentificado.
 userNotFoundMessage=Usuario no encontrado.
 incorrectPasswordMessage=La contraseña actual no es correcta.
 usernameExistsMessage=El nuevo nombre de usuario está en uso.
+deleteCurrentUserMessage=No se puede eliminar el usuario actualmente conectado.
+deleteUsernameExistsMessage=El nombre de usuario no existe y no se puede eliminar.
 
 
 ###############

src/main/resources/messages_eu_ES.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=User not authenticated.
 userNotFoundMessage=User not found.
 incorrectPasswordMessage=Current password is incorrect.
 usernameExistsMessage=New Username already exists.
+deleteCurrentUserMessage=Ezin da ezabatu saioa hasita dagoen erabiltzailea.
+deleteUsernameExistsMessage=Erabiltzaile izena ez dago eta ezin da ezabatu.
 
 
 ###############

src/main/resources/messages_fr_FR.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=Utilisateur non authentifié.
 userNotFoundMessage=Utilisateur non trouvé.
 incorrectPasswordMessage=Le mot de passe actuel est incorrect.
 usernameExistsMessage=Le nouveau nom d\u2019utilisateur existe déjà.
+deleteCurrentUserMessage=Impossible de supprimer l'utilisateur actuellement connecté.
+deleteUsernameExistsMessage=Le nom d'utilisateur n'existe pas et ne peut pas être supprimé.
 
 
 ###############

src/main/resources/messages_hi_IN.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=उपयोगकर्ता प्रमाणित
 userNotFoundMessage=उपयोगकर्ता नहीं मिला।
 incorrectPasswordMessage=वर्तमान पासवर्ड गलत है।
 usernameExistsMessage=नया उपयोगकर्ता नाम पहले से मौजूद है।
+deleteCurrentUserMessage=वर्तमान में लॉग इन उपयोगकर्ता को हटाया नहीं जा सकता.
+deleteUsernameExistsMessage=उपयोगकर्ता नाम मौजूद नहीं है और उसे हटाया नहीं जा सकता.
 
 
 ###############

src/main/resources/messages_hu_HU.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=Felhasználó nincs hitelesítve.
 userNotFoundMessage=A felhasználó nem található.
 incorrectPasswordMessage=A jelenlegi jelszó helytelen.
 usernameExistsMessage=Az új felhasználónév már létezik.
+deleteCurrentUserMessage=A jelenleg bejelentkezett felhasználót nem lehet törölni.
+deleteUsernameExistsMessage=A felhasználónév nem létezik és nem törölhető.
 
 
 ###############

src/main/resources/messages_id_ID.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=Pengguna tidak ter-autentikasi.
 userNotFoundMessage=Pengguna tidak ditemukan.
 incorrectPasswordMessage=Kata sandi saat ini salah.
 usernameExistsMessage=Nama pengguna baru sudah ada.
+deleteCurrentUserMessage=Tidak dapat menghapus pengguna yang sedang login.
+deleteUsernameExistsMessage=Nama pengguna tidak ada dan tidak dapat dihapus.
 
 
 ###############

src/main/resources/messages_it_IT.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=Utente non autenticato.
 userNotFoundMessage=Utente non trovato.
 incorrectPasswordMessage=La password attuale non è corretta.
 usernameExistsMessage=Il nuovo nome utente esiste già.
+deleteCurrentUserMessage=Impossibile eliminare l'utente attualmente connesso.
+deleteUsernameExistsMessage=Il nome utente non esiste e non può essere eliminato.
 
 
 ###############

src/main/resources/messages_ja_JP.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=ユーザーが認証されていません。
 userNotFoundMessage=ユーザーが見つかりません。
 incorrectPasswordMessage=現在のパスワードが正しくありません。
 usernameExistsMessage=新しいユーザー名はすでに存在します。
+deleteCurrentUserMessage=現在ログインしているユーザーは削除できません。
+deleteUsernameExistsMessage=ユーザー名は存在しないため、削除できません。
 
 
 ###############

src/main/resources/messages_ko_KR.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=User not authenticated.
 userNotFoundMessage=사용자를 찾을 수 없습니다.
 incorrectPasswordMessage=현재 비밀번호가 틀립니다.
 usernameExistsMessage=새 사용자명이 이미 존재합니다.
+deleteCurrentUserMessage=현재 로그인된 사용자를 삭제할 수 없습니다.
+deleteUsernameExistsMessage=사용자 이름이 존재하지 않으며 삭제할 수 없습니다.
 
 
 ###############

src/main/resources/messages_nl_NL.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=Gebruiker niet ingelogd.
 userNotFoundMessage=Gebruiker niet gevonden.
 incorrectPasswordMessage=Huidige wachtwoord is onjuist.
 usernameExistsMessage=Nieuwe gebruikersnaam bestaat al.
+deleteCurrentUserMessage=Kan momenteel ingelogde gebruiker niet verwijderen.
+deleteUsernameExistsMessage=De gebruikersnaam bestaat niet en kan niet worden verwijderd.
 
 
 ###############

src/main/resources/messages_pl_PL.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=User not authenticated.
 userNotFoundMessage=User not found.
 incorrectPasswordMessage=Current password is incorrect.
 usernameExistsMessage=New Username already exists.
+deleteCurrentUserMessage=Nie można usunąć aktualnie zalogowanego użytkownika.
+deleteUsernameExistsMessage=Nazwa użytkownika nie istnieje i nie można jej usunąć.
 
 
 ###############

src/main/resources/messages_pt_BR.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=User not authenticated.
 userNotFoundMessage=User not found.
 incorrectPasswordMessage=Current password is incorrect.
 usernameExistsMessage=New Username already exists.
+deleteCurrentUserMessage=Não é possível excluir o usuário conectado no momento.
+deleteUsernameExistsMessage=O nome de usuário não existe e não pode ser excluído.
 
 
 ###############

src/main/resources/messages_pt_PT.properties

@@ -52,6 +52,8 @@ notAuthenticatedMessage=Utilizador não autenticado.
 userNotFoundMessage=Utilizador inexistente.
 incorrectPasswordMessage=Senha incorreta.
 usernameExistsMessage=Esse utilizador já existe.
+deleteCurrentUserMessage=Não é possível excluir o usuário conectado no momento.
+deleteUsernameExistsMessage=O nome de usuário não existe e não pode ser excluído.
 
 
 ###############

src/main/resources/messages_ro_RO.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=User not authenticated.
 userNotFoundMessage=User not found.
 incorrectPasswordMessage=Current password is incorrect.
 usernameExistsMessage=New Username already exists.
+deleteCurrentUserMessage=Nu se poate șterge utilizatorul conectat în prezent.
+deleteUsernameExistsMessage=Numele de utilizator nu există și nu poate fi șters.
 
 
 ###############

src/main/resources/messages_ru_RU.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=User not authenticated.
 userNotFoundMessage=User not found.
 incorrectPasswordMessage=Current password is incorrect.
 usernameExistsMessage=New Username already exists.
+deleteCurrentUserMessage=Невозможно удалить вошедшего в систему пользователя.
+deleteUsernameExistsMessage=Имя пользователя не существует и не может быть удалено.
 
 
 ###############

src/main/resources/messages_sr_LATN_RS.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=Korisnik nije autentifikovan.
 userNotFoundMessage=Korisnik nije pronađen.
 incorrectPasswordMessage=Trenutna šifra je netačna.
 usernameExistsMessage=Novi korisnik već postoji
+deleteCurrentUserMessage=Није могуће избрисати тренутно пријављеног корисника.
+deleteUsernameExistsMessage=Корисничко име не постоји и не може се избрисати.
 
 
 ###############

src/main/resources/messages_sv_SE.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=User not authenticated.
 userNotFoundMessage=User not found.
 incorrectPasswordMessage=Current password is incorrect.
 usernameExistsMessage=New Username already exists.
+deleteCurrentUserMessage=Kan inte ta bort inloggad användare.
+deleteUsernameExistsMessage=Användarnamnet finns inte och kan inte raderas.
 
 
 ###############

src/main/resources/messages_tr_TR.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=Kullanıcı doğrulanmadı.
 userNotFoundMessage=Kullanıcı bulunamadı.
 incorrectPasswordMessage=Mevcut şifre yanlış.
 usernameExistsMessage=Yeni Kullanıcı Adı zaten var.
+deleteCurrentUserMessage=Şu anda oturum açmış olan kullanıcı silinemiyor.
+deleteUsernameExistsMessage=Kullanıcı adı mevcut değil ve silinemez.
 
 
 ###############

src/main/resources/messages_zh_CN.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=用户未经过身份验证。
 userNotFoundMessage=未找到用户。
 incorrectPasswordMessage=当前密码不正确。
 usernameExistsMessage=新用户名已存在。
+deleteCurrentUserMessage=无法删除当前登录的用户。
+deleteUsernameExistsMessage=用户名不存在，无法删除。
 
 
 ###############

src/main/resources/messages_zh_TW.properties

@@ -53,6 +53,8 @@ notAuthenticatedMessage=使用者未認證。
 userNotFoundMessage=找不到使用者。
 incorrectPasswordMessage=目前密碼不正確。
 usernameExistsMessage=新使用者名稱已存在。
+deleteCurrentUserMessage=無法刪除目前登入的使用者。
+deleteUsernameExistsMessage=使用者名稱不存在，無法刪除。
 
 
 ###############

src/main/resources/templates/addUsers.html

@@ -16,6 +16,10 @@
 
               <!-- User Settings Title -->
               <h2 class="text-center" th:text="#{adminUserSettings.header}">Admin User Control Settings</h2>
+              <div th:if="${param.messageType != null and param.messageType.size() > 0 and (param.messageType[0] == 'deleteCurrentUser' or param.messageType[0] == 'deleteUsernameExists')}" class="alert alert-danger">
+                <span th:if="${param.messageType[0] == 'deleteCurrentUser'}" th:text="#{deleteCurrentUserMessage}">Cannot delete currently logged in user.</span>
+                <span th:if="${param.messageType[0] == 'deleteUsernameExists'}" th:text="#{deleteUsernameExistsMessage}">The username does not exist and cannot be deleted.</span>
+              </div>
               <table class="table">
                 <thead>
                   <tr>