diff --git a/photoslibraryapi/src/main/java/com/google/photos/library/v1/upload/UploadMediaItemRequest.java b/photoslibraryapi/src/main/java/com/google/photos/library/v1/upload/UploadMediaItemRequest.java
index 5674ba3..973f383 100644
--- a/photoslibraryapi/src/main/java/com/google/photos/library/v1/upload/UploadMediaItemRequest.java
+++ b/photoslibraryapi/src/main/java/com/google/photos/library/v1/upload/UploadMediaItemRequest.java
@@ -119,13 +119,13 @@ private Builder() {
 
     public Builder mergeFrom(UploadMediaItemRequest other) {
 
-      if (!other.getFileName().isEmpty()) {
+      if (!other.getFileName().isPresent()) {
         fileName = other.fileName;
       }
-      if (!other.getMimeType().isEmpty()) {
+      if (!other.getMimeType().isPresent()) {
         mimeType = other.mimeType;
       }
-      if (!other.getUploadUrl().isEmpty()) {
+      if (!other.getUploadUrl().isPresent()) {
         uploadUrl = other.uploadUrl;
       }
       chunkSize = other.getChunkSize();
diff --git a/sample/src/main/java/com/google/photos/library/sample/demos/upload/tasks/ByteUploadTask.java b/sample/src/main/java/com/google/photos/library/sample/demos/upload/tasks/ByteUploadTask.java
index c54eb17..478efc7 100644
--- a/sample/src/main/java/com/google/photos/library/sample/demos/upload/tasks/ByteUploadTask.java
+++ b/sample/src/main/java/com/google/photos/library/sample/demos/upload/tasks/ByteUploadTask.java
@@ -103,7 +103,7 @@ public ByteUploadResult call() {
       // Upload the bytes and capture the response from the API.
       UploadMediaItemResponse uploadResponse = photosLibraryClient.uploadMediaItem(uploadRequest);
 
-      if (uploadResponse.getUploadToken().isPresent() && uploadResponse.getError().isEmpty()) {
+      if (uploadResponse.getUploadToken().isPresent() && uploadResponse.getError().isPresent()) {
         // The upload was successful, because an upload token is present and there was no error.
         final String uploadToken = uploadResponse.getUploadToken().get();
         return ByteUploadResult.createSuccessResult(fileToUpload, uploadToken);