diff --git a/hawkbit-artifact/hawkbit-artifact-repository-filesystem/src/test/java/org/eclipse/hawkbit/artifact/repository/ArtifactFilesystemRepositoryTest.java b/hawkbit-artifact/hawkbit-artifact-repository-filesystem/src/test/java/org/eclipse/hawkbit/artifact/repository/ArtifactFilesystemRepositoryTest.java
index e5c235729f..5c3a702b35 100644
--- a/hawkbit-artifact/hawkbit-artifact-repository-filesystem/src/test/java/org/eclipse/hawkbit/artifact/repository/ArtifactFilesystemRepositoryTest.java
+++ b/hawkbit-artifact/hawkbit-artifact-repository-filesystem/src/test/java/org/eclipse/hawkbit/artifact/repository/ArtifactFilesystemRepositoryTest.java
@@ -71,7 +71,7 @@ void storeSuccessfully() throws IOException {
 
     @Test
     @Description("Verifies that an artifact can be successfully stored in the file-system repository")
-    void getStoredArtifactBasedOnSHA1Hash() {
+    void getStoredArtifactBasedOnSHA1Hash() throws IOException {
         final byte[] fileContent = randomBytes();
         final AbstractDbArtifact artifact = storeRandomArtifact(fileContent);
 
@@ -80,7 +80,7 @@ void getStoredArtifactBasedOnSHA1Hash() {
 
     @Test
     @Description("Verifies that an artifact can be deleted in the file-system repository")
-    void deleteStoredArtifactBySHA1Hash() {
+    void deleteStoredArtifactBySHA1Hash() throws IOException {
         final AbstractDbArtifact artifact = storeRandomArtifact(randomBytes());
         artifactFilesystemRepository.deleteBySha1(TENANT, artifact.getHashes().getSha1());
 
@@ -89,7 +89,7 @@ void deleteStoredArtifactBySHA1Hash() {
 
     @Test
     @Description("Verifies that all artifacts of a tenant can be deleted in the file-system repository")
-    void deleteStoredArtifactOfTenant() {
+    void deleteStoredArtifactOfTenant() throws IOException {
         final AbstractDbArtifact artifact = storeRandomArtifact(randomBytes());
         artifactFilesystemRepository.deleteByTenant(TENANT);
 
@@ -98,7 +98,7 @@ void deleteStoredArtifactOfTenant() {
 
     @Test
     @Description("Verfies that an artifact which does not exists is deleted quietly in the file-system repository")
-    void deleteArtifactWhichDoesNotExistsBySHA1HashWithoutException() {
+    void deleteArtifactWhichDoesNotExistsBySHA1HashWithoutException() throws IOException {
         try {
             artifactFilesystemRepository.deleteBySha1(TENANT, "sha1HashWhichDoesNotExists");
         } catch (final Exception e) {
@@ -119,17 +119,9 @@ private static byte[] randomBytes() {
         return randomBytes;
     }
 
-    private AbstractDbArtifact storeRandomArtifact(final byte[] fileContent) {
-        final ByteArrayInputStream inputStream = new ByteArrayInputStream(fileContent);
-        try {
+    private AbstractDbArtifact storeRandomArtifact(final byte[] fileContent) throws IOException {
+        try (final ByteArrayInputStream inputStream = new ByteArrayInputStream(fileContent)) {
             return artifactFilesystemRepository.store(TENANT, inputStream, "filename.tmp", "application/txt", null);
-        } finally {
-            try {
-                inputStream.close();
-            } catch (final IOException e) {
-                // do nothing
-                // still return the artifact
-            }
         }
     }
 }
\ No newline at end of file
diff --git a/hawkbit-repository/hawkbit-repository-jpa/src/main/java/org/eclipse/hawkbit/repository/jpa/repository/BaseEntityRepositoryACM.java b/hawkbit-repository/hawkbit-repository-jpa/src/main/java/org/eclipse/hawkbit/repository/jpa/repository/BaseEntityRepositoryACM.java
index a1b695840b..3b1f2ee751 100644
--- a/hawkbit-repository/hawkbit-repository-jpa/src/main/java/org/eclipse/hawkbit/repository/jpa/repository/BaseEntityRepositoryACM.java
+++ b/hawkbit-repository/hawkbit-repository-jpa/src/main/java/org/eclipse/hawkbit/repository/jpa/repository/BaseEntityRepositoryACM.java
@@ -345,17 +345,6 @@ static <T extends AbstractJpaTenantAwareBaseEntity, R extends BaseEntityReposito
         return acmProxy;
     }
 
-    private static <T> boolean isOperationAllowed(
-            final AccessController.Operation operation, T entity,
-            final AccessController<T> accessController) {
-        try {
-            accessController.assertOperationAllowed(operation, entity);
-            return true;
-        } catch (final InsufficientPermissionException e) {
-            return false;
-        }
-    }
-
     @SuppressWarnings({ "rawtypes", "unchecked" })
     private static <T extends Long> Set<Long> toSetDistinct(final Iterable<T> i) {
         final Set<Long> set = new HashSet<>();
diff --git a/hawkbit-repository/hawkbit-repository-jpa/src/test/java/org/eclipse/hawkbit/repository/jpa/management/TargetManagementTest.java b/hawkbit-repository/hawkbit-repository-jpa/src/test/java/org/eclipse/hawkbit/repository/jpa/management/TargetManagementTest.java
index 18e4b9fcda..1c8f63ad87 100644
--- a/hawkbit-repository/hawkbit-repository-jpa/src/test/java/org/eclipse/hawkbit/repository/jpa/management/TargetManagementTest.java
+++ b/hawkbit-repository/hawkbit-repository-jpa/src/test/java/org/eclipse/hawkbit/repository/jpa/management/TargetManagementTest.java
@@ -58,7 +58,6 @@
 import org.eclipse.hawkbit.repository.exception.InvalidTargetAddressException;
 import org.eclipse.hawkbit.repository.exception.RSQLParameterSyntaxException;
 import org.eclipse.hawkbit.repository.exception.RSQLParameterUnsupportedFieldException;
-import org.eclipse.hawkbit.repository.exception.TenantNotExistException;
 import org.eclipse.hawkbit.repository.jpa.AbstractJpaIntegrationTest;
 import org.eclipse.hawkbit.repository.jpa.model.JpaAction;
 import org.eclipse.hawkbit.repository.jpa.model.JpaTarget;
@@ -791,8 +790,7 @@ void createTargetMetadata() {
     @Test
     @Description("Verifies the enforcement of the metadata quota per target.")
     void createTargetMetadataUntilQuotaIsExceeded() {
-
-        // add meta data one by one
+        // add meta-data one by one
         final Target target1 = testdataFactory.createTarget("target1");
         final int maxMetaData = quotaManagement.getMaxMetaDataEntriesPerTarget();
         for (int i = 0; i < maxMetaData; ++i) {
@@ -815,7 +813,7 @@ void createTargetMetadataUntilQuotaIsExceeded() {
 
         // add some meta data entries
         final Target target3 = testdataFactory.createTarget("target3");
-        final int firstHalf = Math.round(maxMetaData / 2);
+        final int firstHalf = maxMetaData / 2;
         for (int i = 0; i < firstHalf; ++i) {
             insertTargetMetadata("k" + i, "v" + i, target3);
         }