Refactor codebase to replace explicit constructors with Lombok annotations and remove boilerplat (#3415)

# Description of Changes

- **What was changed:**  
- Removed explicit constructor definitions annotated with `@Autowired`
across services, controllers, filters, and schedulers.
- Added Lombok’s `@RequiredArgsConstructor` to automatically generate
required-args constructors and eliminate boilerplate.
- Introduced other Lombok annotations (`@Data`, `@Getter`, `@Setter`,
`@EqualsAndHashCode`, `@NoArgsConstructor`) on model and API classes to
replace manual getters/setters and constructors.
- Standardized string comparisons to use the constant-first form (e.g.,
`"value".equals(variable)`).
- Cleaned up unused imports and organized OpenAPI configuration by
extracting default title/description constants.

- **Why the change was made:**  
  - To reduce repetitive boilerplate code and improve maintainability.  
- To leverage Lombok for cleaner, more consistent dependency injection
and data modeling.
  - To ensure a uniform coding style across the entire codebase.

#3406

---

## Checklist

### General

- [x] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [ ] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md)
(if applicable)
- [ ] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md)
(if applicable)
- [x] I have performed a self-review of my own code  
- [x] My changes generate no new warnings  

### Documentation

- [ ] I have updated relevant docs on [Stirling-PDF's doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
- [ ] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

### UI Changes (if applicable)

- [ ] Screenshots or videos demonstrating the UI changes are attached  

### Testing (if applicable)

- [ ] I have tested my changes locally. Refer to the [Testing
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md#6-testing)
for more details.

src/main/java/stirling/software/SPDF/config/security/AppUpdateAuthService.java

@@ -6,24 +6,21 @@ import org.springframework.security.core.Authentication;
 import org.springframework.security.core.context.SecurityContextHolder;
 import org.springframework.stereotype.Service;
 
+import lombok.RequiredArgsConstructor;
+
 import stirling.software.SPDF.config.interfaces.ShowAdminInterface;
 import stirling.software.SPDF.model.ApplicationProperties;
 import stirling.software.SPDF.model.User;
 import stirling.software.SPDF.repository.UserRepository;
 
 @Service
+@RequiredArgsConstructor
 class AppUpdateAuthService implements ShowAdminInterface {
 
     private final UserRepository userRepository;
 
     private final ApplicationProperties applicationProperties;
 
-    public AppUpdateAuthService(
-            UserRepository userRepository, ApplicationProperties applicationProperties) {
-        this.userRepository = userRepository;
-        this.applicationProperties = applicationProperties;
-    }
-
     @Override
     public boolean getShowUpdateOnlyAdmins() {
         boolean showUpdate = applicationProperties.getSystem().isShowUpdate();
@@ -35,7 +32,7 @@ class AppUpdateAuthService implements ShowAdminInterface {
         if (authentication == null || !authentication.isAuthenticated()) {
             return !showUpdateOnlyAdmin;
         }
-        if (authentication.getName().equalsIgnoreCase("anonymousUser")) {
+        if ("anonymousUser".equalsIgnoreCase(authentication.getName())) {
             return !showUpdateOnlyAdmin;
         }
         Optional<User> user = userRepository.findByUsername(authentication.getName());

src/main/java/stirling/software/SPDF/config/security/CustomLogoutSuccessHandler.java

@@ -19,7 +19,7 @@ import com.coveo.saml.SamlException;
 import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
 
-import lombok.AllArgsConstructor;
+import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.SPDF.SPDFApplication;
@@ -32,7 +32,7 @@ import stirling.software.SPDF.model.provider.KeycloakProvider;
 import stirling.software.SPDF.utils.UrlUtils;
 
 @Slf4j
-@AllArgsConstructor
+@RequiredArgsConstructor
 public class CustomLogoutSuccessHandler extends SimpleUrlLogoutSuccessHandler {
 
     public static final String LOGOUT_PATH = "/login?logout=true";

src/main/java/stirling/software/SPDF/config/security/CustomUserDetailsService.java

@@ -11,23 +11,20 @@ import org.springframework.security.core.userdetails.UserDetailsService;
 import org.springframework.security.core.userdetails.UsernameNotFoundException;
 import org.springframework.stereotype.Service;
 
+import lombok.RequiredArgsConstructor;
+
 import stirling.software.SPDF.model.Authority;
 import stirling.software.SPDF.model.User;
 import stirling.software.SPDF.repository.UserRepository;
 
 @Service
+@RequiredArgsConstructor
 public class CustomUserDetailsService implements UserDetailsService {
 
     private final UserRepository userRepository;
 
     private final LoginAttemptService loginAttemptService;
 
-    public CustomUserDetailsService(
-            UserRepository userRepository, LoginAttemptService loginAttemptService) {
-        this.userRepository = userRepository;
-        this.loginAttemptService = loginAttemptService;
-    }
-
     @Override
     public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
         User user =

src/main/java/stirling/software/SPDF/config/security/IPRateLimitingFilter.java

@@ -7,8 +7,11 @@ import java.util.concurrent.atomic.AtomicInteger;
 import jakarta.servlet.*;
 import jakarta.servlet.http.HttpServletRequest;
 
+import lombok.RequiredArgsConstructor;
+
 import stirling.software.SPDF.utils.RequestUriUtils;
 
+@RequiredArgsConstructor
 public class IPRateLimitingFilter implements Filter {
 
     private final ConcurrentHashMap<String, AtomicInteger> requestCounts =
@@ -17,11 +20,6 @@ public class IPRateLimitingFilter implements Filter {
     private final int maxRequests;
     private final int maxGetRequests;
 
-    public IPRateLimitingFilter(int maxRequests, int maxGetRequests) {
-        this.maxRequests = maxRequests;
-        this.maxGetRequests = maxGetRequests;
-    }
-
     @Override
     public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
             throws IOException, ServletException {

src/main/java/stirling/software/SPDF/config/security/InitialSecuritySetup.java

@@ -7,6 +7,7 @@ import org.springframework.stereotype.Component;
 
 import jakarta.annotation.PostConstruct;
 
+import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.SPDF.config.interfaces.DatabaseInterface;
@@ -16,6 +17,7 @@ import stirling.software.SPDF.model.exception.UnsupportedProviderException;
 
 @Slf4j
 @Component
+@RequiredArgsConstructor
 public class InitialSecuritySetup {
 
     private final UserService userService;
@@ -24,15 +26,6 @@ public class InitialSecuritySetup {
 
     private final DatabaseInterface databaseService;
 
-    public InitialSecuritySetup(
-            UserService userService,
-            ApplicationProperties applicationProperties,
-            DatabaseInterface databaseService) {
-        this.userService = userService;
-        this.applicationProperties = applicationProperties;
-        this.databaseService = databaseService;
-    }
-
     @PostConstruct
     public void init() {
         try {

src/main/java/stirling/software/SPDF/config/security/LoginAttemptService.java

@@ -7,6 +7,7 @@ import org.springframework.stereotype.Service;
 
 import jakarta.annotation.PostConstruct;
 
+import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.SPDF.model.ApplicationProperties;
@@ -14,6 +15,7 @@ import stirling.software.SPDF.model.AttemptCounter;
 
 @Service
 @Slf4j
+@RequiredArgsConstructor
 public class LoginAttemptService {
 
     private final ApplicationProperties applicationProperties;
@@ -26,10 +28,6 @@ public class LoginAttemptService {
 
     private boolean isBlockedEnabled = true;
 
-    public LoginAttemptService(ApplicationProperties applicationProperties) {
-        this.applicationProperties = applicationProperties;
-    }
-
     @PostConstruct
     public void init() {
         MAX_ATTEMPT = applicationProperties.getSecurity().getLoginAttemptCount();

src/main/java/stirling/software/SPDF/config/security/RateLimitResetScheduler.java

@@ -3,15 +3,14 @@ package stirling.software.SPDF.config.security;
 import org.springframework.scheduling.annotation.Scheduled;
 import org.springframework.stereotype.Component;
 
+import lombok.RequiredArgsConstructor;
+
 @Component
+@RequiredArgsConstructor
 public class RateLimitResetScheduler {
 
     private final IPRateLimitingFilter rateLimitingFilter;
 
-    public RateLimitResetScheduler(IPRateLimitingFilter rateLimitingFilter) {
-        this.rateLimitingFilter = rateLimitingFilter;
-    }
-
     @Scheduled(cron = "0 0 0 * * MON") // At 00:00 every Monday TODO: configurable
     public void resetRateLimit() {
         rateLimitingFilter.resetRequestCounts();

src/main/java/stirling/software/SPDF/config/security/UserService.java

@@ -19,6 +19,7 @@ import org.springframework.security.oauth2.core.user.OAuth2User;
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 
+import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.SPDF.config.interfaces.DatabaseInterface;
@@ -32,6 +33,7 @@ import stirling.software.SPDF.repository.UserRepository;
 
 @Service
 @Slf4j
+@RequiredArgsConstructor
 public class UserService implements UserServiceInterface {
 
     private final UserRepository userRepository;
@@ -48,23 +50,6 @@ public class UserService implements UserServiceInterface {
 
     private final ApplicationProperties applicationProperties;
 
-    public UserService(
-            UserRepository userRepository,
-            AuthorityRepository authorityRepository,
-            PasswordEncoder passwordEncoder,
-            MessageSource messageSource,
-            SessionPersistentRegistry sessionRegistry,
-            DatabaseInterface databaseService,
-            ApplicationProperties applicationProperties) {
-        this.userRepository = userRepository;
-        this.authorityRepository = authorityRepository;
-        this.passwordEncoder = passwordEncoder;
-        this.messageSource = messageSource;
-        this.sessionRegistry = sessionRegistry;
-        this.databaseService = databaseService;
-        this.applicationProperties = applicationProperties;
-    }
-
     @Transactional
     public void migrateOauth2ToSSO() {
         userRepository

src/main/java/stirling/software/SPDF/config/security/database/ScheduledTasks.java

@@ -6,20 +6,19 @@ import org.springframework.context.annotation.Conditional;
 import org.springframework.scheduling.annotation.Scheduled;
 import org.springframework.stereotype.Component;
 
+import lombok.RequiredArgsConstructor;
+
 import stirling.software.SPDF.config.interfaces.DatabaseInterface;
 import stirling.software.SPDF.controller.api.H2SQLCondition;
 import stirling.software.SPDF.model.exception.UnsupportedProviderException;
 
 @Component
 @Conditional(H2SQLCondition.class)
+@RequiredArgsConstructor
 public class ScheduledTasks {
 
     private final DatabaseInterface databaseService;
 
-    public ScheduledTasks(DatabaseInterface databaseService) {
-        this.databaseService = databaseService;
-    }
-
     @Scheduled(cron = "0 0 0 * * ?")
     public void performBackup() throws SQLException, UnsupportedProviderException {
         databaseService.exportDatabase();

src/main/java/stirling/software/SPDF/config/security/oauth2/CustomOAuth2AuthenticationSuccessHandler.java

@@ -15,6 +15,8 @@ import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
 import jakarta.servlet.http.HttpSession;
 
+import lombok.RequiredArgsConstructor;
+
 import stirling.software.SPDF.config.security.LoginAttemptService;
 import stirling.software.SPDF.config.security.UserService;
 import stirling.software.SPDF.model.ApplicationProperties;
@@ -23,6 +25,7 @@ import stirling.software.SPDF.model.AuthenticationType;
 import stirling.software.SPDF.model.exception.UnsupportedProviderException;
 import stirling.software.SPDF.utils.RequestUriUtils;
 
+@RequiredArgsConstructor
 public class CustomOAuth2AuthenticationSuccessHandler
         extends SavedRequestAwareAuthenticationSuccessHandler {
 
@@ -30,15 +33,6 @@ public class CustomOAuth2AuthenticationSuccessHandler
     private final ApplicationProperties applicationProperties;
     private final UserService userService;
 
-    public CustomOAuth2AuthenticationSuccessHandler(
-            LoginAttemptService loginAttemptService,
-            ApplicationProperties applicationProperties,
-            UserService userService) {
-        this.applicationProperties = applicationProperties;
-        this.userService = userService;
-        this.loginAttemptService = loginAttemptService;
-    }
-
     @Override
     public void onAuthenticationSuccess(
             HttpServletRequest request, HttpServletResponse response, Authentication authentication)

src/main/java/stirling/software/SPDF/config/security/saml2/CustomSaml2ResponseAuthenticationConverter.java

@@ -13,6 +13,7 @@ import org.springframework.security.core.authority.SimpleGrantedAuthority;
 import org.springframework.security.saml2.provider.service.authentication.OpenSaml4AuthenticationProvider.ResponseToken;
 import org.springframework.security.saml2.provider.service.authentication.Saml2Authentication;
 
+import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.SPDF.config.security.UserService;
@@ -20,15 +21,12 @@ import stirling.software.SPDF.model.User;
 
 @Slf4j
 @ConditionalOnProperty(name = "security.saml2.enabled", havingValue = "true")
+@RequiredArgsConstructor
 public class CustomSaml2ResponseAuthenticationConverter
         implements Converter<ResponseToken, Saml2Authentication> {
 
     private final UserService userService;
 
-    public CustomSaml2ResponseAuthenticationConverter(UserService userService) {
-        this.userService = userService;
-    }
-
     private Map<String, List<Object>> extractAttributes(Assertion assertion) {
         Map<String, List<Object>> attributes = new HashMap<>();
 

src/main/java/stirling/software/SPDF/config/security/saml2/SAML2Configuration.java

@@ -21,6 +21,7 @@ import org.springframework.security.saml2.provider.service.web.authentication.Op
 
 import jakarta.servlet.http.HttpServletRequest;
 
+import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.SPDF.model.ApplicationProperties;
@@ -29,14 +30,11 @@ import stirling.software.SPDF.model.ApplicationProperties.Security.SAML2;
 @Configuration
 @Slf4j
 @ConditionalOnProperty(value = "security.saml2.enabled", havingValue = "true")
+@RequiredArgsConstructor
 public class SAML2Configuration {
 
     private final ApplicationProperties applicationProperties;
 
-    public SAML2Configuration(ApplicationProperties applicationProperties) {
-        this.applicationProperties = applicationProperties;
-    }
-
     @Bean
     @ConditionalOnProperty(name = "security.saml2.enabled", havingValue = "true")
     public RelyingPartyRegistrationRepository relyingPartyRegistrations() throws Exception {

src/main/java/stirling/software/SPDF/config/security/session/CustomHttpSessionListener.java

@@ -1,6 +1,5 @@
 package stirling.software.SPDF.config.security.session;
 
-import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Component;
 
 import jakarta.servlet.http.HttpSessionEvent;
@@ -14,7 +13,6 @@ public class CustomHttpSessionListener implements HttpSessionListener {
 
     private SessionPersistentRegistry sessionPersistentRegistry;
 
-    @Autowired
     public CustomHttpSessionListener(SessionPersistentRegistry sessionPersistentRegistry) {
         super();
         this.sessionPersistentRegistry = sessionPersistentRegistry;

src/main/java/stirling/software/SPDF/config/security/session/SessionPersistentRegistry.java

@@ -12,10 +12,13 @@ import org.springframework.stereotype.Component;
 
 import jakarta.transaction.Transactional;
 
+import lombok.RequiredArgsConstructor;
+
 import stirling.software.SPDF.config.security.saml2.CustomSaml2AuthenticatedPrincipal;
 import stirling.software.SPDF.model.SessionEntity;
 
 @Component
+@RequiredArgsConstructor
 public class SessionPersistentRegistry implements SessionRegistry {
 
     private final SessionRepository sessionRepository;
@@ -23,10 +26,6 @@ public class SessionPersistentRegistry implements SessionRegistry {
     @Value("${server.servlet.session.timeout:30m}")
     private Duration defaultMaxInactiveInterval;
 
-    public SessionPersistentRegistry(SessionRepository sessionRepository) {
-        this.sessionRepository = sessionRepository;
-    }
-
     @Override
     public List<Object> getAllPrincipals() {
         List<SessionEntity> sessions = sessionRepository.findAll();

src/main/java/stirling/software/SPDF/config/security/session/SessionScheduled.java

@@ -9,15 +9,14 @@ import org.springframework.scheduling.annotation.Scheduled;
 import org.springframework.security.core.session.SessionInformation;
 import org.springframework.stereotype.Component;
 
+import lombok.RequiredArgsConstructor;
+
 @Component
+@RequiredArgsConstructor
 public class SessionScheduled {
 
     private final SessionPersistentRegistry sessionPersistentRegistry;
 
-    public SessionScheduled(SessionPersistentRegistry sessionPersistentRegistry) {
-        this.sessionPersistentRegistry = sessionPersistentRegistry;
-    }
-
     @Scheduled(cron = "0 0/5 * * * ?")
     public void expireSessions() {
         Instant now = Instant.now();