FWItemAccessorFactory Class Reference

#include <Fireworks/Core/interface/FWItemAccessorFactory.h>

Public Member Functions
boost::shared_ptr < FWItemAccessorBase >	accessorFor (const TClass *) const
	FWItemAccessorFactory ()
virtual	~FWItemAccessorFactory ()

Static Public Member Functions
static bool	classAccessedAsCollection (const TClass *)
static bool	hasAccessor (const TClass *iClass, std::string &result)
static bool	hasMemberTVirtualCollectionProxy (const TClass *iClass, TClass *&oMember, size_t &oOffset)
static bool	hasTVirtualCollectionProxy (const TClass *iClass)

Private Member Functions
	FWItemAccessorFactory (const FWItemAccessorFactory &)
const FWItemAccessorFactory &	operator= (const FWItemAccessorFactory &)

Detailed Description

Description: Factory for constructing FWItemAccessorBases appropriate to a certain type

Usage: <usage>

Definition at line 31 of file FWItemAccessorFactory.h.

Constructor & Destructor Documentation

FWItemAccessorFactory::FWItemAccessorFactory

(

)

Definition at line 38 of file FWItemAccessorFactory.cc.

{
}

FWItemAccessorFactory::~FWItemAccessorFactory ( )

virtual

Definition at line 47 of file FWItemAccessorFactory.cc.

{
}

FWItemAccessorFactory::FWItemAccessorFactory ( const FWItemAccessorFactory &  )

private

Member Function Documentation

boost::shared_ptr< FWItemAccessorBase > FWItemAccessorFactory::accessorFor

(

const TClass *

iClass

)

const

Create an accessor for a given type iClass.

iClass the type for which we need an accessor.

If the type is known to ROOT to be some sort of collection, we return the a FWItemTVirtualCollectionProxyAccessor constructed using the associated TVirtualCollectionProxy.

If the type is not a collection but it contains only one element which is a collection, we return a FWItemTVirtualCollectionProxyAccessor using the TVirtualCollectionProxy of that element.

If none of the above is true, we lookup the plugin based FWItemAccessorRegistry for a plugin that can handle the given type.

Failing that, we return a FWItemSingleAccessor which threats the object as if it was not a collection. Notice that this also will mean that the product associated to iClass will not show up in the "Add Collection" table.

Definition at line 94 of file FWItemAccessorFactory.cc.

References debug, fwLog, reco::get(), hasAccessor(), hasMemberTVirtualCollectionProxy(), hasTVirtualCollectionProxy(), fwlog::kDebug, evf::evtn::offset(), and AlCaHLTBitMon_QueryRunRegistry::string.

Referenced by FWSimpleRepresentationChecker::infoFor().

{
   static const bool debug = false;

   TClass *member = 0;
   size_t offset=0;

   if(hasTVirtualCollectionProxy(iClass)) 
   {
      if (debug)
         fwLog(fwlog::kDebug) << "class " << iClass->GetName()
                              << " uses FWItemTVirtualCollectionProxyAccessor." << std::endl;
      return boost::shared_ptr<FWItemAccessorBase>(
         new FWItemTVirtualCollectionProxyAccessor(iClass,
            boost::shared_ptr<TVirtualCollectionProxy>(iClass->GetCollectionProxy()->Generate())));
   } 
   else if (hasMemberTVirtualCollectionProxy(iClass, member,offset)) 
   {
      if (debug)
         fwLog(fwlog::kDebug) << "class "<< iClass->GetName()
                              << " only contains data member " << member->GetName()
                              << " which uses FWItemTVirtualCollectionProxyAccessor."
                              << std::endl;
       
      return boost::shared_ptr<FWItemAccessorBase>(
         new FWItemTVirtualCollectionProxyAccessor(iClass,
            boost::shared_ptr<TVirtualCollectionProxy>(member->GetCollectionProxy()->Generate()),
                                                   offset));
   }
   
   // Iterate on the available plugins and use the one which handles 
   // the iClass type. 
   // NOTE: This is done only a few times, not really performance critical.
   // If you want this to be fast, the loop can be moved in the 
   // constructor. Notice that this will require constructing FWEventItemsManager 
   // after the plugin manager (i.e. invoking AutoLibraryLoader::enable()) is configured
   // (i.e. invoking AutoLibraryLoader::enable()) in CmsShowMain.
   std::string accessorName;
   if (hasAccessor(iClass, accessorName))
   {
      if (debug)
         fwLog(fwlog::kDebug) << "class " << iClass->GetName() << " uses " 
                              << accessorName << "." << std::endl;
      return boost::shared_ptr<FWItemAccessorBase>(FWItemAccessorRegistry::get()->create(accessorName, iClass));
   }
   
   return boost::shared_ptr<FWItemAccessorBase>(new FWItemSingleAccessor(iClass));
}

bool FWItemAccessorFactory::classAccessedAsCollection ( const TClass *  iClass )

static

Helper method which checks if the object will be treated as a collection.

Returns

true if this is the case, false otherwise.

Definition at line 228 of file FWItemAccessorFactory.cc.

References hasAccessor(), hasMemberTVirtualCollectionProxy(), hasTVirtualCollectionProxy(), evf::evtn::offset(), and AlCaHLTBitMon_QueryRunRegistry::string.

Referenced by FWFFMetadataManager::doUpdate(), and FWLiteJobMetadataManager::doUpdate().

{
   std::string accessorName;
   TClass *member = 0;
   size_t offset=0;
   
   // This is pretty much the same thing that happens 
   return (FWItemAccessorFactory::hasTVirtualCollectionProxy(iClass) 
           || FWItemAccessorFactory::hasMemberTVirtualCollectionProxy(iClass, member,offset)
           || FWItemAccessorFactory::hasAccessor(iClass, accessorName));
}

bool FWItemAccessorFactory::hasAccessor ( const TClass *  iClass, std::string &  result  )

static

Helper method which can be used to retrieve the name of the accessor plugin which has to be created for a object of type iClass.

The result is stored in the passed reference result.

Returns

true if the plugin coul be found, false otherwise.

Definition at line 205 of file FWItemAccessorFactory.cc.

References edmplugin::PluginManager::categoryToInfos(), alignCSCRings::e, edmplugin::PluginManager::get(), i, mergeVDriftHistosByStation::name, and AlCaHLTBitMon_QueryRunRegistry::string.

Referenced by accessorFor(), and classAccessedAsCollection().

{
   const std::vector<edmplugin::PluginInfo> &available
      = edmplugin::PluginManager::get()->categoryToInfos().find("cmsShow FWItemAccessorBase")->second;
   
   for (size_t i = 0, e = available.size(); i != e; ++i)
   {
      std::string name = available[i].name_;
      std::string type = name.substr(0, name.find_first_of('@'));
      if (iClass->GetTypeInfo()->name() == type)
      {
         result.swap(name);
         return true;
      }
   }
   return false;
}

bool FWItemAccessorFactory::hasMemberTVirtualCollectionProxy ( const TClass *  iClass, TClass *&  oMember, size_t &  oOffset  )

static

Helper method which checks if the object has only one data member and if that data memeber can be accessed via a TVirtualCollectionProxy.

oMember a reference to the pointer which will hold the actual TClass of the datamember to be used to build the TVirtualCollectionProxy.

a reference which will hold the offset of the member relative to the beginning address of a class instance.

Returns

true if this is the case, false otherwise.

Definition at line 169 of file FWItemAccessorFactory.cc.

References edm::TypeDataMembers::begin(), dtTPAnalyzer_cfg::dataType, hasTVirtualCollectionProxy(), and edm::TypeDataMembers::size().

Referenced by accessorFor(), and classAccessedAsCollection().

{
   assert(iClass->GetTypeInfo());
   edm::TypeWithDict dataType(*(iClass->GetTypeInfo()));
   assert(bool(dataType));

   // If the object has more than one data member, we avoid guessing. 
   edm::TypeDataMembers members(dataType);
   if (members.size() != 1)
      return false;
   
   edm::MemberWithDict member(*members.begin());
   edm::TypeWithDict memType(member.typeOf());
   assert(bool(memType));
   oMember = TClass::GetClass(memType.typeInfo());
   oOffset = member.offset();
   
   // Check if this is a collection known by ROOT but also that the item held by
   // the colletion actually has a dictionary  
            
   if (!hasTVirtualCollectionProxy(oMember))
      return false;

   return true;
}

bool FWItemAccessorFactory::hasTVirtualCollectionProxy ( const TClass *  iClass )

static

Helper method which

Returns

true if the passes iClass can be accessed via TVirtualCollectionProxy.

Definition at line 147 of file FWItemAccessorFactory.cc.

Referenced by accessorFor(), classAccessedAsCollection(), and hasMemberTVirtualCollectionProxy().

{
   // Check if this is a collection known by ROOT but also that the item held by
   // the colletion actually has a dictionary  
   return iClass &&
          iClass->GetCollectionProxy() && 
          iClass->GetCollectionProxy()->GetValueClass() &&
          iClass->GetCollectionProxy()->GetValueClass()->IsLoaded();
}

const FWItemAccessorFactory& FWItemAccessorFactory::operator= ( const FWItemAccessorFactory &  )

private