due to problems with jaxb there are sometimes nulls

CHANGELOG

+minerva (14.0.0~beta.0) unstable; urgency=low
+  * Bug fix: fetching list of miRnas resulted sometimes in "Internal Server 
+    Error" (#889)
+
+ -- Piotr Gawron <piotr.gawron@uni.lu>  Mon, 21 Aug 2019 21:00:00 +0200
+
 minerva (14.0.0~alpha.1) unstable; urgency=low
   * Feature removal: support for tomcat7 removed (#828)
   * Small improvement: debian package can be installed on debian:buster (#879)

annotation/src/main/java/lcsb/mapviewer/annotation/services/ChemicalParser.java

@@ -362,9 +362,11 @@ public class ChemicalParser extends CachableInterface implements IExternalServic
     if (chemicalNode != null && chemicalNode.hasChildNodes()) {
       try {
         result = chemicalSerializer.xmlToObject(chemicalNode);
-        return result;
       } catch (SerializationException e) {
-        logger.error(e, e);
+        logger.error("Problem with deserializing element", e);
+      }
+      if (result != null) {
+        return result;
       }
     }
     try {

annotation/src/main/java/lcsb/mapviewer/annotation/services/MiRNAParser.java

@@ -190,8 +190,10 @@ public class MiRNAParser extends CachableInterface implements IExternalService {
       Node miRNANode = super.getCacheNode(MI_RNA_PREFIX + name.toLowerCase());
       if (miRNANode != null && miRNANode.hasChildNodes()) {
         miRNA = miRnaSerializer.xmlToObject(miRNANode);
-        miRNAs.add(miRNA);
-        idsToRemove.add(name);
+        if (miRNA != null) {
+          miRNAs.add(miRNA);
+          idsToRemove.add(name);
+        }
       }
     }
     List<String> idsToFind = new ArrayList<>();