diff --git a/haas-spim-benchmark/src/main/java/cz/it4i/fiji/haas_spim_benchmark/ui/SPIMPipelineProgressViewController.java b/haas-spim-benchmark/src/main/java/cz/it4i/fiji/haas_spim_benchmark/ui/SPIMPipelineProgressViewController.java
index c9fed7101d07c9a4dca9da4cfb52432cababbe19..d98267be41f4e9391891f8e0b343795470e6d914 100644
--- a/haas-spim-benchmark/src/main/java/cz/it4i/fiji/haas_spim_benchmark/ui/SPIMPipelineProgressViewController.java
+++ b/haas-spim-benchmark/src/main/java/cz/it4i/fiji/haas_spim_benchmark/ui/SPIMPipelineProgressViewController.java
@@ -6,6 +6,7 @@ import java.awt.event.WindowEvent;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Timer;
 import java.util.TimerTask;
 import java.util.function.Function;