define variables to be used in hashset

src/main/java/org/kpmp/spatialViewerDataset/SpatialViewerExternalLinkDatasetDisplay.java

@@ -1,6 +1,7 @@
 package org.kpmp.spatialViewerDataset;
 
 import java.util.ArrayList;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
 
@@ -56,7 +57,26 @@ public SpatialViewerExternalLinkDatasetDisplay(SpatialViewerExternalLinkDataset
         dataType = svLink.getDataType();
         spectrackSampleId = svLink.getSpectrackSampleId();
         participantId = svLink.getParticipantId();
-
+        redcapId = new HashSet<String>();
+        age = new HashSet<String>();
+        protocol = new HashSet<String>();
+        sampleType = new HashSet<String>();
+        sex = new HashSet<String>();
+        tissueSource = new HashSet<String>();
+        enrollmentCategory = new HashSet<String>();
+        primaryAdjudicatedCategory = new HashSet<String>();
+        kdigoStage = new HashSet<String>();
+        baselineEgfr = new HashSet<String>();
+        proteinuria = new HashSet<String>();
+        a1c = new HashSet<String>();
+        albuminuria = new HashSet<String>();
+        diabetesHistory = new HashSet<String>();
+        diabetesDuration = new HashSet<String>();
+        hypertensionHistory = new HashSet<String>();
+        hypertensionDuration = new HashSet<String>();
+        onRaasBlockade = new HashSet<String>();
+        race = new HashSet<String>();
+
 
         redcapId.add(svLink.getId().getRedcapId());
         if(shouldAdd(svLink.getAge())){