    // @(#)root/tree:$Name:  $:$Id: TBranchBrowsable.cxx,v 1.5 2005/05/18 21:04:54 brun Exp $
    // Author: Axel Naumann   14/10/2004

    /*************************************************************************
     * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers.               *
     * All rights reserved.                                                  *
     *                                                                       *
     * For the licensing terms see $ROOTSYS/LICENSE.                         *
     * For the list of contributors see $ROOTSYS/README/CREDITS.             *
     *************************************************************************/

    #include "TBranchBrowsable.h"
    #include "TBranchElement.h"
    #include "TBranchObject.h"
    #include "TMethod.h"
    #include "TBrowser.h"
    #include "TTree.h"
    #include "TLeafObject.h"
    #include "TPad.h"
    #include "TClass.h"
    #include "TBaseClass.h"
    #include "TDataMember.h"
    #include "TStreamerElement.h"
    #include "TVirtualCollectionProxy.h"
    #include "TRef.h"
    #include <algorithm>

    R__EXTERN TTree *gTree;

    ClassImp(TVirtualBranchBrowsable);

    //______________________________________________________________________________
    //
    // TVirtualBranchBrowsable is a base class (not really abstract, but useless
    // by itself) for helper objects that extend TBranch's browsing support.
    // Each registered derived class's generator method is called, which fills
    // all created helper objects into a list which can then be browsed.
    // For details of what these browser helper objects can do, see e.g.
    // TMethodBrowsable, which allows methods to show up in the TBrowser.
    //
    // Only registered helper objects are created. By default, only
    // TMethodBrowsable, TNonSplitBrowsable, and TCollectionPropertyBrowsable
    // are registered (see RegisterDefaultGenerators). You can prevent any of
    // their objects to show up in the browser by unregistering the generator:
    //   TMethodBrowsable::Unregister()
    // will stop creating browsable method helper objects from that call on.
    // Note that these helper objects are cached (in TBranch::fBrowsables);
    // already created (and thus cached) browsables will still appear in the
    // browser even after unregistering the corresponding generator.
    //
    // You can implement your own browsable objects and thier generator; see
    // e.g. the simple TCollectionPropertyBrowsable. Note that you will have
    // to register your generator just like any other, and that you should
    // implement the following methods for your own class, mainly for
    // consistency reasons:
    //   static void Register() {
    //     TVirtualBranchBrowsable::RegisterGenerator(GetBrowsables); }
    //   static void Unregister() {
    //     TVirtualBranchBrowsable::UnregisterGenerator(GetBrowsables); }
    // where GetBrowsables is a static member function of your class, that
    // creates the browsable helper objects, and has the signature
    //   static Int_t GetBrowsables(TList& list, const TBranch* branch,
    //                              const TVirtualBranchBrowsable* parent=0);
    // It has to return the number of browsable helper objects for parent
    // (or, if NULL, for branch) which are added to the list.
    //______________________________________________________________________________

    std::list<TVirtualBranchBrowsable::MethodCreateListOfBrowsables_t>
       TVirtualBranchBrowsable::fgGenerators;
    Bool_t TVirtualBranchBrowsable::fgGeneratorsSet=kFALSE;

    //______________________________________________________________________________
    TVirtualBranchBrowsable::TVirtualBranchBrowsable(const TBranch* branch, TClass* type,
                                                     Bool_t typeIsPointer,
                                                     const TVirtualBranchBrowsable* parent /*=0*/):
    fBranch(branch), fParent(parent), fLeaves(0), fClass(type), fTypeIsPointer(typeIsPointer) {
       // constructor setting all members according to parameters.
       if (!fgGeneratorsSet) RegisterDefaultGenerators();
       if (!branch)
          Warning("TVirtualBranchBrowsable", "branch is NULL!");
    }

    //______________________________________________________________________________
    TVirtualBranchBrowsable::~TVirtualBranchBrowsable() {
       // Destructor. Delete our leaves.
       delete fLeaves;
    }

    //______________________________________________________________________________
    void TVirtualBranchBrowsable::Browse(TBrowser *b) {
    // Calls TTree::Draw on the method if return type is not a class;
    // otherwise expands returned object's "folder"

       if (!fClass) {
          TString name;
          GetScope(name);

          // If this is meant to be run on the collection
          // we need to "move" the "@" from branch.@member
          // to branch@.member
          name.ReplaceAll(".@","@.");
          name.ReplaceAll("->@","@->");

          TTree* tree=0;
          if (!fBranch) {
             Warning("Browse", "branch not set - might access wrong tree!");
             tree=gTree;
          } else tree=fBranch->GetTree();
          tree->Draw(name, "", b ? b->GetDrawOption() : "");
          if (gPad) gPad->Update();
       } else
          if (GetLeaves()) GetLeaves()->Browse(b);
    }

    //______________________________________________________________________________
    Int_t TVirtualBranchBrowsable::FillListOfBrowsables(TList& li, const TBranch* branch,
       const TVirtualBranchBrowsable* parent /* =0 */) {
    // Askes all registered generators to fill their browsables into
    // the list. The browsables are generated for a given parent,
    // or (if 0), for a given branch. The branch is passed down to
    // leaves of TVirtualBranchBrowsable, too, as we need to access
    // the branch's TTree to be able to traw.
       if (!fgGeneratorsSet) RegisterDefaultGenerators();
       std::list<MethodCreateListOfBrowsables_t>::iterator iGenerator;
       Int_t numCreated=0;
       for (iGenerator=fgGenerators.begin(); iGenerator!=fgGenerators.end(); iGenerator++)
          numCreated+=(*(*iGenerator))(li, branch, parent);
       return numCreated;
    }

    //______________________________________________________________________________
    TClass* TVirtualBranchBrowsable::GetCollectionContainedType(const TBranch* branch,
                                                                const TVirtualBranchBrowsable* parent,
                                                                TClass* &contained) {
    // Check whether the branch (or the parent) contains a collection.
    // If it does, set "contained" to the contained type (if we can
    // retrieve it) and return the TClass for the collection. Set
    // "contained" to the branch's (or parent's) contained object's
    // class for non-collections, returning 0.
    //
    // Only one of "branch" or "parent" can ge given (depending on whether
    // we are creating browsable objects for a branch or for another
    // browsable object)
       contained=0;
       TClass* type=0;
       if (parent)
          type=parent->GetClassType();
       else if (branch) {
          if (branch->IsA()==TBranchElement::Class()) {
             // could be a split TClonesArray
             TBranchElement* be=(TBranchElement*) branch;

             // this is the contained type - if !=0
             const char* clonesname=be->GetClonesName();
             if (clonesname && strlen(clonesname))
                contained=gROOT->GetClass(clonesname);

             // check if we're in a sub-branch of this class
             // we can only find out asking the streamer given our ID
             ULong_t *elems=0;
             TStreamerElement *element=0;
             if (be->GetID()>=0 && be->GetInfo()
                && ((elems=be->GetInfo()->GetElems()))
                && ((element=(TStreamerElement *)elems[be->GetID()]))) {
                // if contained is set (i.e. GetClonesName was successful),
                // this element containes the container, otherwise it's the
                // contained
                if (contained)
                   // we have all we need
                   return element->GetClassPointer();
                else
                   type=element->GetClassPointer();
             } else if (clonesname && strlen(clonesname)) {
                // we have a clones name, and the TCA is not split:
                contained=gROOT->GetClass(clonesname);
                return gROOT->GetClass(be->GetClassName());
             } else
                type=gROOT->GetClass(be->GetClassName());
          } else if (branch->IsA()==TBranchObject::Class()) {
             // could be an unsplit TClonesArray
             TBranchObject* bo=(TBranchObject*)branch;
             const char* clonesname=bo->GetClassName();
             contained=0;
             if (!clonesname || !strlen(clonesname)) return 0;
             type=gROOT->GetClass(clonesname);
          }
       } else {
          if (gTree) gTree->Warning("GetCollectionContainedType", "Neither branch nor parent given!");
          return 0;
       }

       if (!type) return 0;

       TBranch* branchNonCost=const_cast<TBranch*>(branch);
       if (type->InheritsFrom(TClonesArray::Class())
          && branch->IsA()==TBranchObject::Class()
          && branchNonCost->GetListOfLeaves()
          && branchNonCost->GetListOfLeaves()->GetEntriesFast()==1) {
          // load first entry of the branch. Yes, this is bad, and might have
          // unexpected side effects for the user, esp as already looking at
          // (and not just drawing) a branch triggeres it.
          // To prove just how ugly it is, we'll also have to const_cast the
          // branch...
          if (branch->GetReadEntry()==-1) branchNonCost->GetEntry(0);
          // now get element
          TLeafObject* lo=(TLeafObject*)branchNonCost->GetListOfLeaves()->First();
          TObject* objContainer=lo->GetObject();
          if (lo && objContainer && objContainer->IsA()==TClonesArray::Class())
             contained=((TClonesArray*)objContainer)->GetClass();
          return type;
       } else    if (type->InheritsFrom(TClonesArray::Class())
          && branch->IsA()==TBranchElement::Class()
          && branchNonCost->GetListOfLeaves()
          && branchNonCost->GetListOfLeaves()->GetEntriesFast()==1) {
          // load first entry of the branch. Yes, this is bad, and might have
          // unexpected side effects for the user, esp as already looking at
          // (and not just drawing) a branch triggeres it.
          // To prove just how ugly it is, we'll also have to const_cast the
          // branch...

          //if (branch->GetReadEntry()==-1) branchNonCost->GetEntry(0);
          // now get element
          //TLeafObject* lo=(TLeafElement*)branchNonCost->GetListOfLeaves()->First();
          //TObject* objContainer=(TObject*)((TBranchElement*)branch)->GetValuePointer();

          //if (objContainer && objContainer->IsA()==TClonesArray::Class())
          //   contained=((TClonesArray*)objContainer)->GetClass();

          // Currently we can peer into the nested TClonesArray, we need
          // to update TBranchElement::GetValuePointer.
          return type;
       } else if (type->InheritsFrom(TCollection::Class())) {
          // some other container, and we don't know what the contained type is
          return type;
       } else if (type->GetCollectionProxy()) {
          contained=type->GetCollectionProxy()->GetValueClass();
          return type;
       } else if (type->InheritsFrom(TRef::Class()))
          // we don't do TRefs, so return contained and container as 0
          return 0;
       else contained=type;
       return 0;
    }

    //______________________________________________________________________________
    TList* TVirtualBranchBrowsable::GetLeaves() const {
    // Return list of leaves. If not set up yet we'll create them.
       if (!fLeaves) {
          TList* leaves=new TList();
          leaves->SetOwner();
          FillListOfBrowsables(*leaves, GetBranch(), this);
          const_cast<TVirtualBranchBrowsable*>(this)->fLeaves=leaves;
       }
       return fLeaves;
    }

    //______________________________________________________________________________
    std::list<TVirtualBranchBrowsable::MethodCreateListOfBrowsables_t>& TVirtualBranchBrowsable::GetRegisteredGenerators() {
       // returns the list of registered generator methods
       return fgGenerators;
    }

    //______________________________________________________________________________
    void TVirtualBranchBrowsable::GetScope(TString & scope) const {
    // Returns the full name for TTree::Draw to draw *this.
    // Recursively appends, starting at the top TBranch,
    // all method / object names with proper reference operators (->, .)
    // depending on fTypeIsPointer.

       if (fParent)
          fParent->GetScope(scope);
       else {
          scope=fBranch->GetName();
          if (!scope.EndsWith(".")) scope+=".";
          const TBranch* mother=fBranch;
          while (mother != mother->GetMother() && (mother=mother->GetMother())) {
             TString nameMother(mother->GetName());
             if (!nameMother.EndsWith(".")) {
                scope.Prepend(".");
                scope.Prepend(nameMother);
             } else {
                if (mother != mother->GetMother()) {
                   // If the mother is the top level mother
                   // and its ends ends with a ., the name is already
                   // embedded!
                   scope.Prepend(nameMother);
                }
             }
          }
       }
       if (GetName() && GetName()[0]=='.')
          scope+=(GetName()+1);
       else
          scope+=GetName();
       if (fClass && !scope.EndsWith(".")) // otherwise we're a leaf, and no delimiter is appended
          if (fTypeIsPointer)
             scope+="->";
          else scope+=".";
    }

    //______________________________________________________________________________
    void TVirtualBranchBrowsable::RegisterDefaultGenerators() {
    // Adds the default generators. The user can remove any of them as follows:
    //   TMethodBrowsable::Unregister();
    // which will cause the browser not to show any methods.
       if (fgGeneratorsSet) return;
       // can't call RegisterGenerator - would be recusive infite loop
       fgGenerators.push_back(&TMethodBrowsable::GetBrowsables);
       fgGenerators.push_back(&TNonSplitBrowsable::GetBrowsables);
       fgGenerators.push_back(&TCollectionPropertyBrowsable::GetBrowsables);
       fgGeneratorsSet=kTRUE;
    }

    void TVirtualBranchBrowsable::RegisterGenerator(MethodCreateListOfBrowsables_t generator) {
       // Adds a generator to be called when browsing branches.
       // Called by the Register method, which should be implemented
       // for all derived classes (see e.g. TMethodBrowsable::Register())
       if (!fgGeneratorsSet) RegisterDefaultGenerators();
       // make sure we're not adding another copy
       fgGenerators.remove(generator);
       fgGenerators.push_back(generator);
    }

    void TVirtualBranchBrowsable::UnregisterGenerator(MethodCreateListOfBrowsables_t generator) {
       // Removes a generator from the list of generators to be called when
       // browsing branches. The user can remove any of the generators as follows:
       //   TMethodBrowsable::Unregister();
       // which will cause the browser not to show any methods.
       if (!fgGeneratorsSet) RegisterDefaultGenerators();
       fgGenerators.remove(generator);
    }

    ClassImp(TMethodBrowsable);

    //______________________________________________________________________________
    //
    //  This helper object allows the browsing of methods of objects stored in
    //  branches. They will be depicted by a leaf (or a branch, in case the method
    //  returns an object) with a red exclamation mark. Only a subset of all
    //  methods will be shown in the browser (see IsMethodBrowsable for the
    //  criteria a method has to satisfy).
    //
    //  Obviously, methods are only available if the library is loaded which
    //  contains the dictionary for the class to be browsed!
    //
    //  If a branch contains a collection, TMethodBrowsable tries to find out
    //  what the contained element is (it will only create methods for the
    //  contained elements, but never for the collection). If it fails to extract
    //  the type of the contained elements, or if there is no guarantee that the
    //  type has any other common denominator than TObject (e.g. in the case of
    //  a TObjArray, which can hold any object deriving from TObject) no methods
    //  will be added.
    //______________________________________________________________________________

    //______________________________________________________________________________
    TMethodBrowsable::TMethodBrowsable(const TBranch* branch, TMethod* m,
                                       const TVirtualBranchBrowsable* parent /* =0 */):
       TVirtualBranchBrowsable(branch, 0, kFALSE, parent), fMethod(m) {
    // Constructor.
    // Links a TBranchElement to a TMethod, allowing the TBrowser to
    // browse simple methods.
    //
    // The c'tor sets the name for a method "Class::Method(params) const"
    // to "Method(params)", title to TMethod::GetPrototype
       TString name(m->GetName());
       name+="()";
       if (name.EndsWith(" const")) name.Remove(name.Length()-6);
       SetName(name);

       name=m->GetPrototype();
       if (m->GetCommentString() && strlen(m->GetCommentString()))
          name.Append(" // ").Append(m->GetCommentString());
       SetTitle(name);

       TString plainReturnType(m->GetReturnTypeName());
       if (plainReturnType.EndsWith("*")) {
          SetTypeIsPointer();
          plainReturnType.Remove(plainReturnType.Length()-1);
          plainReturnType.Strip();
          if(plainReturnType.BeginsWith("const")) {
            plainReturnType.Remove(0,5);
            plainReturnType.Strip();
          }
       }
       SetType(gROOT->GetClass(plainReturnType));
    }

    //______________________________________________________________________________
    void TMethodBrowsable::GetBrowsableMethodsForClass(TClass* cl, TList& li) {
    // Given a class, this methods fills list with TMethodBrowsables
    // for the class and its base classes, and returns the number of
    // added elements. If called from a TBranch::Browse overload, "branch"
    // should be set to the calling TBranch, otherwise "parent" should
    // be set to the TVirtualBranchBrowsable being browsed, and branch
    // should be the branch of the parent.

       if (!cl) return;
       TList allClasses;
       allClasses.Add(cl);

       for(TObjLink* lnk=allClasses.FirstLink();
           lnk; lnk=lnk->Next()){
          cl=(TClass*)lnk->GetObject();
          TList* bases=cl->GetListOfBases();
          TBaseClass* base;
          TIter iB(bases);
          while ((base=(TBaseClass*)iB())) {
             TClass* bc=base->GetClassPointer();
             if (bc) allClasses.Add(bc);
          }
       }

       TList allMethods;
       TIter iC(&allClasses);
       while ((cl=(TClass*)iC())) {
          TList* methods=cl->GetListOfMethods();
          if (!methods) continue;
          TMethod* method=0;
          TIter iM(methods);
          while ((method=(TMethod*)iM()))
             if (method && !allMethods.FindObject(method->GetName()))
                 allMethods.Add(method);
       }

       TIter iM(&allMethods);
       TMethod* m=0;
       while ((m=(TMethod*)iM()))
          if (TMethodBrowsable::IsMethodBrowsable(m))
             li.Add(m);
    }

    //______________________________________________________________________________
    Int_t TMethodBrowsable::GetBrowsables(TList& li, const TBranch* branch,
                                          const TVirtualBranchBrowsable* parent /*=0*/) {
    // This methods fills list with TMethodBrowsables
    // for the branch's or parent's class and its base classes, and returns
    // the number of added elements. If called from a TBranch::Browse
    // overload, "branch" should be set to the calling TBranch, otherwise
    // "parent" should be set to the TVirtualBranchBrowsable being browsed.
       TClass* cl;
       // we don't care about collections, so only use the TClass argument,
       // and not the return value
       GetCollectionContainedType(branch, parent, cl);
       if (!cl) return 0;

       TList listMethods;
       GetBrowsableMethodsForClass(cl, listMethods);
       TMethod* method=0;
       TIter iMethods(&listMethods);
       while ((method=(TMethod*)iMethods()))
          li.Add(new TMethodBrowsable(branch, method, parent));
       return listMethods.GetSize();
    }

    //______________________________________________________________________________
    Bool_t TMethodBrowsable::IsMethodBrowsable(const TMethod* m) {
    // A TMethod is browsable if it is const, public and not pure virtual,
    // if does not have any parameter without default value, and if it has
    // a (non-void) return value.
    // A method called *, Get*, or get* will not be browsable if there is a
    // persistent data member called f*, _*, or m*, as data member access is
    // faster than method access. Examples: if one of fX, _X, or mX is a
    // persistent data member, the methods GetX(), getX(), and X() will not
    // be browsable.

       if (m->GetNargs()-m->GetNargsOpt()==0
           && (m->Property() & kIsConstant
               & ~kIsPrivate & ~kIsProtected & ~kIsPureVirtual )
           && m->GetReturnTypeName()
           && strcmp("void",m->GetReturnTypeName())
           && !strstr(m->GetName(),"DeclFile")
           && !strstr(m->GetName(),"ImplFile")
           && strcmp(m->GetName(),"IsA")
           && strcmp(m->GetName(),"Class")
           && strcmp(m->GetName(),"CanBypassStreamer")
           && strcmp(m->GetName(),"Class_Name")
           && strcmp(m->GetName(),"ClassName")
           && strcmp(m->GetName(),"Clone")
           && strcmp(m->GetName(),"DrawClone")
           && strcmp(m->GetName(),"GetName")
           && strcmp(m->GetName(),"GetDrawOption")
           && strcmp(m->GetName(),"GetIconName")
           && strcmp(m->GetName(),"GetOption")
           && strcmp(m->GetName(),"GetTitle")
           && strcmp(m->GetName(),"GetUniqueID")
           && strcmp(m->GetName(),"Hash")
           && strcmp(m->GetName(),"IsFolder")
           && strcmp(m->GetName(),"IsOnHeap")
           && strcmp(m->GetName(),"IsSortable")
           && strcmp(m->GetName(),"IsZombie")) {
             // look for matching data member
             TClass* cl=m->GetClass();
             if (!cl) return kTRUE;
             TList* members=cl->GetListOfDataMembers();
             if (!members) return kTRUE;
             const char* baseName=m->GetName();
             if (!strncmp(m->GetName(), "Get", 3) ||
                 !strncmp(m->GetName(), "get", 3))
                baseName+=3;
             if (!baseName[0]) return kTRUE;

             TObject* mem=0;
             const char* arrMemberNames[3]={"f%s","_%s","m%s"};
             for (Int_t i=0; !mem && i<3; i++)
                mem=members->FindObject(Form(arrMemberNames[i],baseName));
             return (!mem ||! ((TDataMember*)mem)->IsPersistent());
       };
       return kFALSE;
    }

    //______________________________________________________________________________
    void TMethodBrowsable::Register() {
       // Wrapper for the registration method. Needed against MSVC, which
       // assigned different addr to the same method, depending on what
       // translation unit you're in...
       TVirtualBranchBrowsable::RegisterGenerator(GetBrowsables);
    }

    //______________________________________________________________________________
    void TMethodBrowsable::Unregister() {
       // Wrapper for the registration method. Needed against MSVC, which
       // assigned different addr to the same method, depending on what
       // translation unit you're in...
       TVirtualBranchBrowsable::UnregisterGenerator(GetBrowsables);
    }

    ClassImp(TNonSplitBrowsable);

    //______________________________________________________________________________
    //
    // Allows a TBrowser to browse non-split branches as if they were split. The
    // generator extracts the necessary information from the streamer info in
    // memory (which does not have to be the same as the one on file, in case
    // a library was loaded containing the dictionary for this type), i.e. it
    // also works without loading the class's library.
    //
    // Just as with TMethodBrowsables, if the generator finds a collection it
    // only takes the contained objects into account, not the collections. If
    // it identifies a collection, but cannot extract the contained type, or the
    // contained type can be anything deriving from a TObject (like for TObjArray)
    // or is not limited at all, no browser helper objects are created.
    //______________________________________________________________________________

    //______________________________________________________________________________
     TNonSplitBrowsable::TNonSplitBrowsable(const TStreamerElement* element, const TBranch* branch,
                                           const TVirtualBranchBrowsable* parent /* =0 */):
       TVirtualBranchBrowsable(branch, element->GetClassPointer(),
       element->IsaPointer(), parent) {
    // Constructor. Creates a TNonSplitBrowsable from a TStreamerElement, containing branch
    // and (if applicable) parent TVirtualBranchBrowsable.
       SetNameTitle(element->GetName(), element->GetTitle());
    }

    //______________________________________________________________________________
     Int_t TNonSplitBrowsable::GetBrowsables(TList& li, const TBranch* branch,
                                            const TVirtualBranchBrowsable* parent /* =0 */)
    {
    // Given either a branch "branch" or a "parent" TVirtualBranchBrowsable, we fill
    // "list" with objects of type TNonSplitBrowsable which represent the members
    // of class "cl" (and its base classes' members).

       // branch has to be unsplit, i.e. without sub-branches
       if (branch && const_cast<TBranch*>(branch)->GetListOfBranches()
          && const_cast<TBranch*>(branch)->GetListOfBranches()->GetEntries()!=0)
          return 0;
       // we only expand our own parents
       //if (parent && parent->IsA()!=TNonSplitBrowsable::Class()) return 0;

       TClass* clContained=0;
       GetCollectionContainedType(branch, parent, clContained);
       TStreamerInfo* streamerInfo=clContained?clContained->GetStreamerInfo():0;
       if (!streamerInfo
          || !streamerInfo->GetElements()
          || !streamerInfo->GetElements()->GetSize())  return 0;

       if (!branch && parent) branch=parent->GetBranch();

       // we simply add all of our and the bases' members into one big list
       TList myStreamerElementsToCheck;
       myStreamerElementsToCheck.AddAll(streamerInfo->GetElements());

       Int_t numAdded=0;
       TIter iStreamerElements(&myStreamerElementsToCheck);
       TStreamerElement* streamerElement=0;
       while ((streamerElement=(TStreamerElement*)iStreamerElements())) {
          if (streamerElement->IsBase()) {
             // this is a base class place holder
             // continue with the base class's streamer info
             TClass* base=streamerElement->GetClassPointer();
             if (!base || !base->GetStreamerInfo()) continue;

             // add all of the base class's streamer elements
             // (which in turn can be a base, which will be
             // unfolded in a later iteration) to the list
             TObjArray* baseElements=base->GetStreamerInfo()->GetElements();
             if (!baseElements) continue;
             TIter iBaseSE(baseElements);
             TStreamerElement* baseSE=0;
             while ((baseSE=(TStreamerElement*)iBaseSE()))
                // we should probably check whether we're replacing something here...
                myStreamerElementsToCheck.Add(baseSE);
          } else if (!strcmp(streamerElement->GetName(),"This")
             && !strcmp(clContained->GetName(), streamerElement->GetTypeName())) {
             // this is a collection of the real elements.
             // So get the class ptr for these elements...
             TClass* clElements=streamerElement->GetClassPointer();
             TVirtualCollectionProxy* collProxy=clElements?clElements->GetCollectionProxy():0;
             clElements=collProxy?collProxy->GetValueClass():0;
             if (!clElements) continue;

             // now loop over the class's streamer elements
             TStreamerInfo* streamerInfo=clElements->GetStreamerInfo();
             TIter iElem(streamerInfo->GetElements());
             TStreamerElement* elem=0;
             while ((elem=(TStreamerElement*)iElem())) {
                TNonSplitBrowsable* nsb=new TNonSplitBrowsable(elem, branch, parent);
                li.Add(nsb);
                numAdded++;
             }
          } else {
             // we have a basic streamer element
             TNonSplitBrowsable* nsb=new TNonSplitBrowsable(streamerElement, branch, parent);
             li.Add(nsb);
             numAdded++;
          }
       }
       return numAdded;
    }

    //______________________________________________________________________________
     void TNonSplitBrowsable::Register() {
       // Wrapper for the registration method. Needed against MSVC, which
       // assigned different addr to the same method, depending on what
       // translation unit you're in...
       TVirtualBranchBrowsable::RegisterGenerator(GetBrowsables);
    }

    //______________________________________________________________________________
     void TNonSplitBrowsable::Unregister() {
       // Wrapper for the registration method. Needed against MSVC, which
       // assigned different addr to the same method, depending on what
       // translation unit you're in...
       TVirtualBranchBrowsable::UnregisterGenerator(GetBrowsables);
    }

    ClassImp(TCollectionPropertyBrowsable);

    //______________________________________________________________________________
    //
    // A tiny browser helper object (and its generator) for adding a virtual
    // (as in "not actually part of the class", not in C++ virtual) "@size()"
    // method to a collection. For all collections that derive from
    // TCollection, or have a TVirtualCollectionProxy associated with them,
    // a leaf is created that allows access to the number of elements in the
    // collection. For TClonesArrays and types with an associated
    // TVirtualCollectionProxy, this forwards to TTreeFormula's
    // "@branch.size()" functionality. For all other collections, a method call
    // to the appropriate collection's member function is executed when drawing.
    //
    // These objects are of course only created for elements containing a
    // collection; the generator has no effect on any other elements.
    //______________________________________________________________________________

    //______________________________________________________________________________
    void TCollectionPropertyBrowsable::Browse(TBrowser *b) {
       // Browses a TCollectionPropertyBrowsable. The only difference to
       // the generic TVirtualBranchBrowsable::Browse is our fDraw
       GetBranch()->GetTree()->Draw(GetDraw(), "", b ? b->GetDrawOption() : "");
       if (gPad) gPad->Update();
    }

    //______________________________________________________________________________
    Int_t TCollectionPropertyBrowsable::GetBrowsables(TList& li, const TBranch* branch,
                                                      const TVirtualBranchBrowsable* parent /* =0 */) {
    // If the element to browse (given by either parent of branch) contains
    // a collection (TClonesArray or something for which a TVirtualCollectionProxy
    // exists), we will add some special objects to the browser. For now there is
    // just one object "@size", returning the size of the collection (as in
    // std::list::size(), or TClonesArray::GetEntries()).
    // The objects we create are simply used to forward strings (like "@size") to
    // TTreeFormula via our Browse method. These strings are stored in fName.
       TClass* clContained=0;
       TClass* clCollection=GetCollectionContainedType(branch, parent, clContained);
       if (!clCollection || !clContained) return 0;

       // Build the fDraw string. Start with our scope.
       TString scope;
       if (parent) {
          parent->GetScope(scope);
          branch=parent->GetBranch();
       } else if (branch){
          scope=branch->GetName();
          scope+=".";
          const TBranch* mother=branch;
          while (mother != mother->GetMother() && (mother=mother->GetMother())) {
             TString nameMother(mother->GetName());
             if (!nameMother.EndsWith(".")) {
                scope.Prepend(".");
                scope.Prepend(nameMother);
             } else {
                if (mother != mother->GetMother()) {
                   // If the mother is the top level mother
                   // and its ends ends with a ., the name is already
                   // embedded!
                   scope.Prepend(nameMother);
                }
             }
          }
       } else {
          if (gTree)
             gTree->Warning("GetBrowsables", "Neither branch nor parent is set!");
          return 0;
       }

       // remove trailing delimiters
       if (scope.EndsWith(".")) scope.Remove(scope.Length()-1, 1);
       else if (scope.EndsWith("->")) scope.Remove(scope.Length()-2, 2);

       // now prepend "@" to the last element of the scope,
       // to access the collection and not its containees
       Ssiz_t lastDot=scope.Last('.');
       Ssiz_t lastArrow=scope.Last('>'); // assuming there's no branch name containing ">"...
       Ssiz_t lastPart=lastDot;
       if (lastPart==kNPOS || lastArrow!=kNPOS && lastPart<lastArrow)
          lastPart=lastArrow;
       if (lastPart==kNPOS) lastPart=0;
       else lastPart++;

       if (clCollection->GetCollectionProxy() || clCollection==TClonesArray::Class()) {
       // the collection is one for which TTree::Draw supports @coll.size()

          scope.Insert(lastPart, "@");
          TCollectionPropertyBrowsable* cpb=
             new TCollectionPropertyBrowsable("@size", "size of the collection",
             scope+".size()", branch, parent);
          li.Add(cpb);
          return 1;
       } // if a collection proxy or TClonesArray
       else if (clCollection->InheritsFrom(TCollection::Class())) {
          // generic TCollection - we'll build size() ourselves, by mapping
          // it to the proper member function of the collection
          if (clCollection->InheritsFrom(TObjArray::Class()))
             scope+="@.GetEntries()";
          else scope+="@.GetSize()";
          TCollectionPropertyBrowsable* cpb=
             new TCollectionPropertyBrowsable("@size", "size of the collection", scope, branch, parent);
          li.Add(cpb);
          return 1;
       }
       return 0;
    }

    //______________________________________________________________________________
    void TCollectionPropertyBrowsable::Register() {
       // Wrapper for the registration method. Needed against MSVC, which
       // assigned different addr to the same method, depending on what
       // translation unit you're in...
       TVirtualBranchBrowsable::RegisterGenerator(GetBrowsables);
    }

    //______________________________________________________________________________
    void TCollectionPropertyBrowsable::Unregister() {
       // Wrapper for the registration method. Needed against MSVC, which
       // assigned different addr to the same method, depending on what
       // translation unit you're in...
       TVirtualBranchBrowsable::UnregisterGenerator(GetBrowsables);
    }

    ClassImp(TCollectionMethodBrowsable);

    //______________________________________________________________________________
    //
    // TCollectionMethodBrowsable extends TCollectionPropertyBrowsable by showing
    // all methods of the collection itself. If none are available - e.g. for STL
    // classes like std::list, a TVirtualBranchBrowsable object is reated instead.
    // The methods' names will have a "@" prepended, to distinguish them from the
    // contained elements' methods.
    //
    // This browser helper object is not part of the default list of registered
    // generators (see TVirtualBranchBrowsable::RegisterDefaultGenerators()).
    // If you want to use it, you should call
    //   TCollectionMethodBrowsable::Register();
    // As it extends the functionality of TVirtualBranchBrowsable, one might want
    // to unregister the generator of the "@size()" method by calling
    //   TCollectionPropertyBrowsable::Unregister();
    //______________________________________________________________________________

    //______________________________________________________________________________
    TCollectionMethodBrowsable::TCollectionMethodBrowsable(const TBranch* branch, TMethod* m,
                                                           const TVirtualBranchBrowsable* parent /*=0*/):
    TMethodBrowsable(branch, m, parent) {
       // Contructor, see TMethodBrowsable's constructor.
       // Prepends "@" to the name to make this method work on the container.
       SetName(TString("@")+GetName());
    }

    //______________________________________________________________________________
    Int_t TCollectionMethodBrowsable::GetBrowsables(TList& li, const TBranch* branch,
                                                    const TVirtualBranchBrowsable* parent /*=0*/) {
    // This methods fills list with TMethodBrowsables
    // for the branch's or parent's collection class and its base classes,
    // and returns the number of added elements. If called from a TBranch::Browse
    // overload, "branch" should be set to the calling TBranch, otherwise
    // "parent" should be set to the TVirtualBranchBrowsable being browsed.
       TClass* clContained=0;
       // we don't care about the contained class, but only about the collections,
       TClass* clContainer=GetCollectionContainedType(branch, parent, clContained);
       if (!clContainer || !clContained) return 0;

       TList listMethods;
       GetBrowsableMethodsForClass(clContainer, listMethods);
       TMethod* method=0;
       TIter iMethods(&listMethods);
       while ((method=(TMethod*)iMethods()))
          li.Add(new TCollectionMethodBrowsable(branch, method, parent));

       // if we have no methods, and if the class has a collection proxy, just add
       // the corresponding TCollectionPropertyBrowsable instead.
       // But only do that if TCollectionPropertyBrowsable is not generatated anyway
       // - we don't need two of them.
       if (!listMethods.GetSize() && clContainer->GetCollectionProxy()) {
          std::list<MethodCreateListOfBrowsables_t>& listGenerators=GetRegisteredGenerators();
          std::list<MethodCreateListOfBrowsables_t>::iterator iIsRegistered
             = std::find(listGenerators.begin(), listGenerators.end(), &TCollectionPropertyBrowsable::GetBrowsables);
          if (iIsRegistered==listGenerators.end()) {
             TCollectionPropertyBrowsable::GetBrowsables(li, branch, parent);
             return 1;
          }
       }
       return listMethods.GetSize();
    }

    //______________________________________________________________________________
    void TCollectionMethodBrowsable::Register() {
       // Wrapper for the registration method. Needed against MSVC, which
       // assigned different addr to the same method, depending on what
       // translation unit you're in...
       TVirtualBranchBrowsable::RegisterGenerator(GetBrowsables);
    }

    //______________________________________________________________________________
    void TCollectionMethodBrowsable::Unregister() {
       // Wrapper for the registration method. Needed against MSVC, which
       // assigned different addr to the same method, depending on what
       // translation unit you're in...
       TVirtualBranchBrowsable::UnregisterGenerator(GetBrowsables);
    }