Made GeneratorHybrid a singleton

Author: jackal1-66

Generators/include/Generators/GeneratorHybrid.h

@@ -54,8 +54,12 @@ class GeneratorHybrid : public Generator
 {
 
  public:
-  GeneratorHybrid(const std::string& inputgens);
-  ~GeneratorHybrid();
+  GeneratorHybrid& operator=(const GeneratorHybrid&) = delete;
+  GeneratorHybrid(const GeneratorHybrid&) = delete;
+
+  // Singleton access methods
+  static GeneratorHybrid& Instance(const std::string& inputgens = "");
+  static GeneratorHybrid* GetInstance(const std::string& inputgens = "");
 
   Bool_t Init() override;
   Bool_t generateEvent() override;
@@ -66,11 +70,13 @@ class GeneratorHybrid : public Generator
   Bool_t confSetter(const auto& gen);
   template <typename T>
   std::string jsonValueToString(const T& value);
-  static std::vector<std::shared_ptr<o2::eventgen::Generator>> const& getGenerators() { return gens; }
+  std::vector<std::shared_ptr<o2::eventgen::Generator>> const& getGenerators() { return gens; }
 
  private:
+  GeneratorHybrid(const std::string& inputgens);
+  ~GeneratorHybrid();
   o2::eventgen::Generator* currentgen = nullptr;
-  static std::vector<std::shared_ptr<o2::eventgen::Generator>> gens;
+  std::vector<std::shared_ptr<o2::eventgen::Generator>> gens;
   const std::vector<std::string> generatorNames = {"extkinO2", "evtpool", "boxgen", "external", "hepmc", "pythia8", "pythia8pp", "pythia8hi", "pythia8hf", "pythia8powheg"};
   std::vector<std::string> mInputGens;
   std::vector<std::string> mGens;

Generators/src/GeneratorFactory.cxx

@@ -284,7 +284,7 @@ void GeneratorFactory::setPrimaryGenerator(o2::conf::SimConfig const& conf, Fair
       LOG(fatal) << "Configuration file for hybrid generator does not exist";
       return;
     }
-    auto hybrid = new o2::eventgen::GeneratorHybrid(config);
+    auto hybrid = o2::eventgen::GeneratorHybrid::GetInstance(config);
     primGen->AddGenerator(hybrid);
 #endif
   } else {

Generators/src/GeneratorHybrid.cxx

@@ -23,7 +23,16 @@ namespace o2
 namespace eventgen
 {
 
-std::vector<std::shared_ptr<o2::eventgen::Generator>> GeneratorHybrid::gens;
+GeneratorHybrid& GeneratorHybrid::Instance(const std::string& inputgens)
+{
+  static GeneratorHybrid instance(inputgens);
+  return instance;
+}
+
+GeneratorHybrid* GeneratorHybrid::GetInstance(const std::string& inputgens)
+{
+  return &Instance(inputgens);
+}
 
 GeneratorHybrid::GeneratorHybrid(const std::string& inputgens)
 {