JavaIsJavaScript
diff --git a/‎src/main/java/de/rwth/idsg/steve/utils/JodaDateTimeConverter.java‎
Lines changed: 12 additions & 2 deletions b/‎src/main/java/de/rwth/idsg/steve/utils/JodaDateTimeConverter.java‎
Lines changed: 12 additions & 2 deletions
@@ -4,6 +4,8 @@
 
 import javax.xml.bind.annotation.adapters.XmlAdapter;
 
+import static com.google.common.base.Strings.isNullOrEmpty;
+
 /**
  * Joda-Time and XSD represent data and time information according to ISO 8601.
  *
@@ -14,11 +16,19 @@ public class JodaDateTimeConverter extends XmlAdapter<String, DateTime> {
 
     @Override
     public DateTime unmarshal(String v) throws Exception {
-        return new DateTime(v);
+        if (isNullOrEmpty(v)) {
+            return null;
+        } else {
+            return new DateTime(v);
+        }
     }
 
     @Override
     public String marshal(DateTime v) throws Exception {
-        return v.toString();
+        if (v == null) {
+            return null;
+        } else {
+            return v.toString();
+        }
     }
 }