diff --git a/hawkbit-artifact/hawkbit-artifact-api/src/main/java/org/eclipse/hawkbit/artifact/repository/urlhandler/PropertyBasedArtifactUrlHandler.java b/hawkbit-artifact/hawkbit-artifact-api/src/main/java/org/eclipse/hawkbit/artifact/repository/urlhandler/PropertyBasedArtifactUrlHandler.java
index 5dbe229c71..dfe3c77f9a 100644
--- a/hawkbit-artifact/hawkbit-artifact-api/src/main/java/org/eclipse/hawkbit/artifact/repository/urlhandler/PropertyBasedArtifactUrlHandler.java
+++ b/hawkbit-artifact/hawkbit-artifact-api/src/main/java/org/eclipse/hawkbit/artifact/repository/urlhandler/PropertyBasedArtifactUrlHandler.java
@@ -62,8 +62,9 @@ public class PropertyBasedArtifactUrlHandler implements ArtifactUrlHandler {
     private static final String TENANT_ID_BASE10_PLACEHOLDER = "tenantId";
     private static final String TENANT_ID_BASE62_PLACEHOLDER = "tenantIdBase62";
     private static final String SOFTWARE_MODULE_ID_BASE10_PLACEHOLDER = "softwareModuleId";
-    final static String DEFAULT_URL_PROTOCOL_REF = "{" + PROTOCOL_PLACEHOLDER + "}://{" + HOSTNAME_PLACEHOLDER + "}:{" + PORT_PLACEHOLDER + "}{" + CONTEXT_PATH + "}/{" + TENANT_PLACEHOLDER + "}/controller/v1/{" + CONTROLLER_ID_PLACEHOLDER + "}/softwaremodules/{" + SOFTWARE_MODULE_ID_BASE10_PLACEHOLDER + "}/artifacts/{" + ARTIFACT_FILENAME_PLACEHOLDER + "}";
     private static final String SOFTWARE_MODULE_ID_BASE62_PLACEHOLDER = "softwareModuleIdBase62";
+    static final String DEFAULT_URL_PROTOCOL_REF = "{" + PROTOCOL_PLACEHOLDER + "}://{" + HOSTNAME_PLACEHOLDER + "}:{" + PORT_PLACEHOLDER + "}{" + CONTEXT_PATH + "}/{" + TENANT_PLACEHOLDER + "}/controller/v1/{" + CONTROLLER_ID_PLACEHOLDER + "}/softwaremodules/{" + SOFTWARE_MODULE_ID_BASE10_PLACEHOLDER + "}/artifacts/{" + ARTIFACT_FILENAME_PLACEHOLDER + "}";
+
     private final ArtifactUrlHandlerProperties urlHandlerProperties;
     private final String contextPath;
 
diff --git a/hawkbit-artifact/hawkbit-artifact-api/src/test/java/org/eclipse/hawkbit/artifact/repository/urlhandler/PropertyBasedArtifactUrlHandlerTest.java b/hawkbit-artifact/hawkbit-artifact-api/src/test/java/org/eclipse/hawkbit/artifact/repository/urlhandler/PropertyBasedArtifactUrlHandlerTest.java
index 504ea979f5..fbcb5bacd0 100644
--- a/hawkbit-artifact/hawkbit-artifact-api/src/test/java/org/eclipse/hawkbit/artifact/repository/urlhandler/PropertyBasedArtifactUrlHandlerTest.java
+++ b/hawkbit-artifact/hawkbit-artifact-api/src/test/java/org/eclipse/hawkbit/artifact/repository/urlhandler/PropertyBasedArtifactUrlHandlerTest.java
@@ -31,7 +31,7 @@
 @Feature("Unit Tests - Artifact URL Handler")
 @Story("Test to generate the artifact download URL")
 @ExtendWith(MockitoExtension.class)
-public class PropertyBasedArtifactUrlHandlerTest {
+class PropertyBasedArtifactUrlHandlerTest {
 
     private static final String TEST_PROTO = "coap";
     private static final String TEST_REL = "download-udp";
@@ -56,14 +56,14 @@ public class PropertyBasedArtifactUrlHandlerTest {
     private ArtifactUrlHandlerProperties properties;
 
     @BeforeEach
-    public void setup() {
+    void setup() {
         properties = new ArtifactUrlHandlerProperties();
         urlHandlerUnderTest = new PropertyBasedArtifactUrlHandler(properties, "");
     }
 
     @Test
     @Description("Tests the generation of http download url.")
-    public void urlGenerationWithDefaultConfiguration() {
+    void urlGenerationWithDefaultConfiguration() {
         properties.getProtocols().put("download-http", new UrlProtocol());
 
         final List<ArtifactUrl> ddiUrls = urlHandlerUnderTest.getUrls(placeHolder, ApiType.DDI);
@@ -78,7 +78,7 @@ public void urlGenerationWithDefaultConfiguration() {
 
     @Test
     @Description("Tests the generation of custom download url with a CoAP example that supports DMF only.")
-    public void urlGenerationWithCustomConfiguration() {
+    void urlGenerationWithCustomConfiguration() {
         final UrlProtocol proto = new UrlProtocol();
         proto.setIp("127.0.0.1");
         proto.setPort(5683);
@@ -97,7 +97,7 @@ public void urlGenerationWithCustomConfiguration() {
 
     @Test
     @Description("Tests the generation of custom download url using Base62 references with a CoAP example that supports DMF only.")
-    public void urlGenerationWithCustomShortConfiguration() {
+    void urlGenerationWithCustomShortConfiguration() {
         final UrlProtocol proto = new UrlProtocol();
         proto.setIp("127.0.0.1");
         proto.setPort(5683);
@@ -116,7 +116,7 @@ public void urlGenerationWithCustomShortConfiguration() {
 
     @Test
     @Description("Verifies that the full qualified host of the statically defined hostname is replaced with the host of the request.")
-    public void urlGenerationWithHostFromRequest() throws URISyntaxException {
+    void urlGenerationWithHostFromRequest() throws URISyntaxException {
         final String testHost = "ddi.host.com";
 
         final UrlProtocol proto = new UrlProtocol();
@@ -136,7 +136,7 @@ public void urlGenerationWithHostFromRequest() throws URISyntaxException {
 
     @Test
     @Description("Verifies that the protocol of the statically defined hostname is replaced with the protocol of the request.")
-    public void urlGenerationWithProtocolFromRequest() throws URISyntaxException {
+    void urlGenerationWithProtocolFromRequest() throws URISyntaxException {
         final String testHost = "ddi.host.com";
 
         final UrlProtocol proto = new UrlProtocol();
@@ -151,7 +151,7 @@ public void urlGenerationWithProtocolFromRequest() throws URISyntaxException {
 
     @Test
     @Description("Verifies that the port of the statically defined hostname is replaced with the port of the request.")
-    public void urlGenerationWithPortFromRequest() throws URISyntaxException {
+    void urlGenerationWithPortFromRequest() throws URISyntaxException {
         final UrlProtocol proto = new UrlProtocol();
         proto.setRef("{protocol}://{hostname}:{portRequest}/{tenant}/controller/v1/{controllerId}/softwaremodules/{softwareModuleId}/artifacts/{artifactFileName}");
 
@@ -172,7 +172,7 @@ public void urlGenerationWithPortFromRequest() throws URISyntaxException {
 
     @Test
     @Description("Verifies that if default protocol port in request is used then url is returned without port")
-    public void urlGenerationWithPortFromRequestForHttps() throws URISyntaxException {
+    void urlGenerationWithPortFromRequestForHttps() throws URISyntaxException {
         final String protocol = "https";
         final UrlProtocol proto = new UrlProtocol();
         proto.setRef("{protocolRequest}://{hostnameRequest}:{portRequest}/{tenant}/controller/v1/{controllerId}/softwaremodules/{softwareModuleId}/artifacts/{artifactFileName}");
@@ -190,7 +190,7 @@ public void urlGenerationWithPortFromRequestForHttps() throws URISyntaxException
 
     @Test
     @Description("Verifies that the domain of the statically defined hostname is replaced with the domain of the request.")
-    public void urlGenerationWithDomainFromRequest() throws URISyntaxException {
+    void urlGenerationWithDomainFromRequest() throws URISyntaxException {
         final UrlProtocol proto = new UrlProtocol();
         proto.setHostname("host.bumlux.net");
         proto.setRef("{protocol}://{domainRequest}/{tenant}/controller/v1/{controllerId}/softwaremodules/{softwareModuleId}/artifacts/{artifactFileName}");
diff --git a/hawkbit-repository/hawkbit-repository-test/src/main/java/org/eclipse/hawkbit/repository/test/TestConfiguration.java b/hawkbit-repository/hawkbit-repository-test/src/main/java/org/eclipse/hawkbit/repository/test/TestConfiguration.java
index 3f826e5caf..24da7db829 100644
--- a/hawkbit-repository/hawkbit-repository-test/src/main/java/org/eclipse/hawkbit/repository/test/TestConfiguration.java
+++ b/hawkbit-repository/hawkbit-repository-test/src/main/java/org/eclipse/hawkbit/repository/test/TestConfiguration.java
@@ -55,7 +55,6 @@
 import org.springframework.cache.caffeine.CaffeineCacheManager;
 import org.springframework.cloud.bus.ConditionalOnBusEnabled;
 import org.springframework.context.ApplicationEvent;
-import org.springframework.context.annotation.AdviceMode;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Profile;
@@ -98,7 +97,7 @@ public AsyncUncaughtExceptionHandler getAsyncUncaughtExceptionHandler() {
     public ScheduledExecutorService scheduledExecutorService() {
         final AtomicLong count = new AtomicLong(0);
         return new DelegatingSecurityContextScheduledExecutorService(
-                Executors.newScheduledThreadPool(1, (runnable) -> {
+                Executors.newScheduledThreadPool(1, runnable -> {
                     final Thread thread = Executors.defaultThreadFactory().newThread(runnable);
                     thread.setName(
                             String.format(
diff --git a/hawkbit-repository/hawkbit-repository-test/src/main/java/org/eclipse/hawkbit/repository/test/util/SecurityContextSwitch.java b/hawkbit-repository/hawkbit-repository-test/src/main/java/org/eclipse/hawkbit/repository/test/util/SecurityContextSwitch.java
index d5979e5548..906adf5d40 100644
--- a/hawkbit-repository/hawkbit-repository-test/src/main/java/org/eclipse/hawkbit/repository/test/util/SecurityContextSwitch.java
+++ b/hawkbit-repository/hawkbit-repository-test/src/main/java/org/eclipse/hawkbit/repository/test/util/SecurityContextSwitch.java
@@ -17,6 +17,8 @@
 import java.util.Objects;
 import java.util.concurrent.Callable;
 
+import lombok.AccessLevel;
+import lombok.NoArgsConstructor;
 import org.eclipse.hawkbit.im.authentication.SpPermission;
 import org.eclipse.hawkbit.tenancy.TenantAwareAuthenticationDetails;
 import org.eclipse.hawkbit.tenancy.TenantAwareUser;
@@ -25,6 +27,7 @@
 import org.springframework.security.core.context.SecurityContext;
 import org.springframework.security.core.context.SecurityContextHolder;
 
+@NoArgsConstructor(access = AccessLevel.PRIVATE)
 public class SecurityContextSwitch {
 
     public static final String DEFAULT_TENANT = "DEFAULT";
diff --git a/hawkbit-repository/hawkbit-repository-test/src/main/java/org/eclipse/hawkbit/repository/test/util/TestdataFactory.java b/hawkbit-repository/hawkbit-repository-test/src/main/java/org/eclipse/hawkbit/repository/test/util/TestdataFactory.java
index d5e1e23ba8..b2fd1998d5 100644
--- a/hawkbit-repository/hawkbit-repository-test/src/main/java/org/eclipse/hawkbit/repository/test/util/TestdataFactory.java
+++ b/hawkbit-repository/hawkbit-repository-test/src/main/java/org/eclipse/hawkbit/repository/test/util/TestdataFactory.java
@@ -13,7 +13,7 @@
 
 import java.io.ByteArrayInputStream;
 import java.io.InputStream;
-import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
 import java.security.SecureRandom;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -359,9 +359,9 @@ public DistributionSet createDistributionSet(final String prefix, final String v
             final boolean isRequiredMigrationStep, final Collection<SoftwareModule> modules) {
 
         return distributionSetManagement.create(
-                entityFactory.distributionSet().create().name(prefix != null && prefix.length() > 0 ? prefix : "DS")
+                entityFactory.distributionSet().create().name(prefix != null && !prefix.isEmpty() ? prefix : "DS")
                         .version(version).description(randomDescriptionShort()).type(findOrCreateDefaultTestDsType())
-                        .modules(modules.stream().map(SoftwareModule::getId).collect(Collectors.toList()))
+                        .modules(modules.stream().map(SoftwareModule::getId).toList())
                         .requiredMigrationStep(isRequiredMigrationStep));
     }
 
@@ -481,7 +481,7 @@ public List<Artifact> createArtifacts(final Long moduleId) {
      * @return {@link Artifact} entity.
      */
     public Artifact createArtifact(final String artifactData, final Long moduleId, final String filename) {
-        final InputStream stubInputStream = IOUtils.toInputStream(artifactData, Charset.forName("UTF-8"));
+        final InputStream stubInputStream = IOUtils.toInputStream(artifactData, StandardCharsets.UTF_8);
         return artifactManagement
                 .create(new ArtifactUpload(stubInputStream, moduleId, filename, false, artifactData.length()));
     }