delete file quietly (#351)

Signed-off-by: Michael Hirsch <michael.hirsch@bosch-si.com>

hawkbit-ui/pom.xml

@@ -171,6 +171,10 @@
          <artifactId>hawkbit-repository-api</artifactId>
          <version>${project.version}</version>
       </dependency>
+      <dependency>
+         <groupId>commons-io</groupId>
+         <artifactId>commons-io</artifactId>
+      </dependency>
       <!-- Vaadin -->
       <dependency>
          <groupId>com.vaadin</groupId>

hawkbit-ui/src/main/java/org/eclipse/hawkbit/ui/artifacts/upload/UploadLayout.java

@@ -20,6 +20,7 @@ import java.util.Set;
 import javax.annotation.PostConstruct;
 import javax.annotation.PreDestroy;
 
+import org.apache.commons.io.FileUtils;
 import org.eclipse.hawkbit.repository.exception.ArtifactUploadFailedException;
 import org.eclipse.hawkbit.repository.model.SoftwareModule;
 import org.eclipse.hawkbit.ui.artifacts.event.SoftwareModuleEvent;
@@ -593,10 +594,7 @@ public class UploadLayout extends VerticalLayout {
     void clearFileList() {
         // delete file system zombies
         artifactUploadState.getFileSelected().forEach(customFile -> {
-            final File file = new File(customFile.getFilePath());
-            if (!file.delete()) {
-                LOG.warn("Failed to delete file {} in upload dialog", customFile.getFilePath());
-            }
+            FileUtils.deleteQuietly(new File(customFile.getFilePath()));
         });
 
         artifactUploadState.getFileSelected().clear();