Merge pull request #2029 from sswguo/hotfix

Fix: Null values are not supported

Author: sswguo

db/cassandra/src/main/java/org/commonjava/indy/cassandra/data/CassandraStoreDataManager.java

@@ -601,13 +601,16 @@ private ArtifactStore computeIfAbsent( String name, StoreKey key, int expiration
             DtxArtifactStore dtxArtifactStore = storeQuery.getArtifactStore( key.getPackageType(), key.getType(), key.getName() );
 
             store = toArtifactStore( dtxArtifactStore );
-            if ( expirationMins > 0 )
-            {
-                cache.put( key, store, expirationMins, TimeUnit.MINUTES );
-            }
-            else
+            if ( store != null )
             {
-                cache.put( key, store );
+                if (expirationMins > 0)
+                {
+                    cache.put(key, store, expirationMins, TimeUnit.MINUTES);
+                }
+                else
+                {
+                    cache.put(key, store);
+                }
             }
         }