00001 #ifndef DataFormats_Common_TestHandle_h 00002 #define DataFormats_Common_TestHandle_h 00003 00004 /*---------------------------------------------------------------------- 00005 00006 TestHandle: Non-owning "smart pointer" for reference to EDProducts. 00007 00008 00009 This is a very preliminary version, and lacks safety features and 00010 elegance. 00011 00012 If the pointed-to EDProduct is destroyed, use of the TestHandle 00013 becomes undefined. There is no way to query the TestHandle to 00014 discover if this has happened. 00015 00016 TestHandles can have: 00017 -- Product pointer null and id == 0; 00018 -- Product pointer valid and id != 0; 00019 00020 To check validity, one can use the isValid() function. 00021 00022 ----------------------------------------------------------------------*/ 00023 00024 #include "DataFormats/Common/interface/OrphanHandleBase.h" 00025 00026 namespace edm { 00027 class EDProduct; 00028 00029 template <typename T> 00030 class TestHandle : public OrphanHandleBase { 00031 public: 00032 typedef T element_type; 00033 00034 // Default constructed handles are invalid. 00035 TestHandle(); 00036 00037 TestHandle(T const* prod, ProductID const& id); 00038 00039 ~TestHandle(); 00040 00041 T const* product() const; 00042 T const* operator->() const; // alias for product() 00043 T const& operator*() const; 00044 00045 private: 00046 }; 00047 00048 template <class T> 00049 TestHandle<T>::TestHandle() : OrphanHandleBase() 00050 { } 00051 00052 template <class T> 00053 TestHandle<T>::TestHandle(T const* prod, ProductID const& theId) : OrphanHandleBase(prod, theId) { 00054 } 00055 00056 template <class T> 00057 TestHandle<T>::~TestHandle() {} 00058 00059 template <class T> 00060 T const* 00061 TestHandle<T>::product() const { 00062 return static_cast<T const*>(productStorage()); 00063 } 00064 00065 template <class T> 00066 T const* 00067 TestHandle<T>::operator->() const { 00068 return product(); 00069 } 00070 00071 template <class T> 00072 T const& 00073 TestHandle<T>::operator*() const { 00074 return *product(); 00075 } 00076 00077 } 00078 #endif