exception

backend/src/main/java/pdl/backend/ImageDao.java

@@ -21,6 +21,8 @@ public class ImageDao implements Dao<Image> {
 	public ImageDao() {
 		try {
 			final var folderPath = new ClassPathResource("images");
+			if (folderPath.exists())
+				throw new ImageResourceMissingException("folderPath is null");
 			final var folder = folderPath.getFile();
 			getAllImages(folder);
 		} catch (final Exception e) {

backend/src/main/java/pdl/backend/ImageResourceMissingException.java

@@ -0,0 +1,9 @@
+package pdl.backend;
+
+import java.io.FileNotFoundException;
+
+public class ImageResourceMissingException extends FileNotFoundException {
+	public ImageResourceMissingException(String message) {
+		super(message);
+	}
+}