Program: 63028
Project: 63028
Buggy source:
private SemanticSignature getSemanticSignature(KnowledgeBase aKB,String aWikidataId){
  if (semanticSignatureCache.containsKey(aWikidataId)) {
    return semanticSignatureCache.get(aWikidataId);
  }
  Set<String> relatedRelations=new HashSet<>();
  Set<String> relatedEntities=new HashSet<>();
  try (RepositoryConnection conn=kbService.getConnection(aKB)){
    TupleQuery query=QueryUtil.generateSemanticSignatureQuery(conn,aWikidataId,properties.getSignatureQueryLimit());
    try (TupleQueryResult result=query.evaluate()){
      while (result.hasNext()) {
        BindingSet sol=result.next();
        String propertyString=sol.getValue("String_Node_Str").stringValue();
        String labelString=sol.getValue("String_Node_Str").stringValue();
        if (propertyWithLabels != null) {
          Property property=propertyWithLabels.get(labelString);
          int frequencyThreshold=0;
          boolean isBlacklisted=(propertyBlacklist != null && propertyBlacklist.contains(propertyString) || (property != null && (typeBlacklist != null && typeBlacklist.contains(property.getType()))));
          boolean isUnfrequent=property != null && property.getFreq() < frequencyThreshold;
          if (isBlacklisted || isUnfrequent) {
            continue;
          }
        }
        relatedEntities.add(labelString);
        relatedRelations.add(propertyString);
      }
    }
 catch (    Exception e) {
      logger.error("String_Node_Str",e);
    }
  }
   SemanticSignature ss=new SemanticSignature(relatedEntities,relatedRelations);
  semanticSignatureCache.put(aWikidataId,ss);
  return ss;
}

Fixed version (ground truth):
private SemanticSignature getSemanticSignature(KnowledgeBase aKB,String aWikidataId){
  ImmutablePair<Project,String> pair=new ImmutablePair<>(aKB.getProject(),aWikidataId);
  if (semanticSignatureCache.containsKey(pair)) {
    return semanticSignatureCache.get(pair);
  }
  Set<String> relatedRelations=new HashSet<>();
  Set<String> relatedEntities=new HashSet<>();
  try (RepositoryConnection conn=kbService.getConnection(aKB)){
    TupleQuery query=QueryUtil.generateSemanticSignatureQuery(conn,aWikidataId,properties.getSignatureQueryLimit());
    try (TupleQueryResult result=query.evaluate()){
      while (result.hasNext()) {
        BindingSet sol=result.next();
        String propertyString=sol.getValue("String_Node_Str").stringValue();
        String labelString=sol.getValue("String_Node_Str").stringValue();
        if (propertyWithLabels != null) {
          Property property=propertyWithLabels.get(labelString);
          int frequencyThreshold=0;
          boolean isBlacklisted=(propertyBlacklist != null && propertyBlacklist.contains(propertyString) || (property != null && (typeBlacklist != null && typeBlacklist.contains(property.getType()))));
          boolean isUnfrequent=property != null && property.getFreq() < frequencyThreshold;
          if (isBlacklisted || isUnfrequent) {
            continue;
          }
        }
        relatedEntities.add(labelString);
        relatedRelations.add(propertyString);
      }
    }
 catch (    Exception e) {
      logger.error("String_Node_Str",e);
    }
  }
   SemanticSignature ss=new SemanticSignature(relatedEntities,relatedRelations);
  semanticSignatureCache.put(pair,ss);
  return ss;
}