diff --git a/generator/src/main/java/com/google/archivepatcher/generator/TempBlob.java b/generator/src/main/java/com/google/archivepatcher/generator/TempBlob.java
index cf93f23e..1de305a4 100644
--- a/generator/src/main/java/com/google/archivepatcher/generator/TempBlob.java
+++ b/generator/src/main/java/com/google/archivepatcher/generator/TempBlob.java
@@ -22,6 +22,7 @@
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.OutputStream;
+import java.util.Optional;
 
 /**
  * A closeable container for a temp blob that deletes itself on {@link #close()}. This is convenient