From f280e60562d5d9924f4abe44644b98299a0a29b3 Mon Sep 17 00:00:00 2001
From: "k.triantafyllou" <k.triantafyllou@di.uoa.gr>
Date: Fri, 4 Aug 2023 15:57:40 +0300
Subject: [PATCH] Fix StringListConverter to add empty string in database
 column if the array is empty.

---
 .../java/eu/dnetlib/developers/utils/StringListConverter.java   | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/main/java/eu/dnetlib/developers/utils/StringListConverter.java b/src/main/java/eu/dnetlib/developers/utils/StringListConverter.java
index 5d63bed..ef1568c 100644
--- a/src/main/java/eu/dnetlib/developers/utils/StringListConverter.java
+++ b/src/main/java/eu/dnetlib/developers/utils/StringListConverter.java
@@ -12,7 +12,7 @@ public class StringListConverter implements AttributeConverter<List<String>, Str
     @Override
     public String convertToDatabaseColumn(List<String> attribute) {
         if (attribute == null || attribute.isEmpty()) {
-            return null;
+            return "";
         }
         return String.join(ARRAY_DELIMITER, attribute);
     }