// @(#)root/tree:$Name: $:$Id: TBranchRef.cxx,v 1.9 2006/03/22 06:36:20 pcanal Exp $ // Author: Rene Brun 19/08/2004 /************************************************************************* * Copyright (C) 1995-2004, Rene Brun and Fons Rademakers. * * All rights reserved. * * * * For the licensing terms see $ROOTSYS/LICENSE. * * For the list of contributors see $ROOTSYS/README/CREDITS. * *************************************************************************/ ////////////////////////////////////////////////////////////////////////// // // // A branch containing and managing a TRefTable for TRef autoloading. // // It loads the TBranch containing a referenced object when requested // // by TRef::GetObject(), so the reference can be resolved. The // // information which branch to load is stored by TRefTable. Once a // // TBranch has read the TBranchRef's current entry it will not be told // // to re-read, in case the use has changed objects read from the // // branch. // // // // // // *** LIMITATION *** // // Note that this does NOT allow for autoloading of references spanning // // different entries. The TBranchRef's current entry has to correspond // // to the entry of the TBranch containing the referenced object. // // // // The TRef cannot be stored in a top-level branch which is a // // TBranchObject for the auto-loading to work. E.g. you cannot store // // the TRefs in TObjArray, and create a top-level branch storing this // // TObjArray. // // // ////////////////////////////////////////////////////////////////////////// #include "TBranchRef.h" #include "TTree.h" #include "TBasket.h" #include "TFile.h" #include "TFriendElement.h" ClassImp(TBranchRef) //______________________________________________________________________________ TBranchRef::TBranchRef(): TBranch() { // Default constructor. fRefTable = 0; } //______________________________________________________________________________ TBranchRef::TBranchRef(TTree *tree) :TBranch() { // Main constructor called by TTree::BranchRef. if (!tree) return; SetName("TRefTable"); SetTitle("List of branch numbers with referenced objects"); fRefTable = new TRefTable(this,100); fCompress = 1; fBasketSize = 32000; fAddress = 0; fBasketBytes = new Int_t[fMaxBaskets]; fBasketEntry = new Long64_t[fMaxBaskets]; fBasketSeek = new Long64_t[fMaxBaskets]; for (Int_t i=0;i<fMaxBaskets;i++) { fBasketBytes[i] = 0; fBasketEntry[i] = 0; fBasketSeek[i] = 0; } fTree = tree; fDirectory = fTree->GetDirectory(); fFileName = ""; // Create the first basket TBasket *basket = new TBasket("TRefTable",fTree->GetName(),this); fBaskets.Add(basket); } //______________________________________________________________________________ TBranchRef::~TBranchRef() { // Typical destructor. delete fRefTable; } //______________________________________________________________________________ void TBranchRef::Clear(Option_t *option) { // Clear entries in the TRefTable. if (fRefTable) fRefTable->Clear(option); } //______________________________________________________________________________ Int_t TBranchRef::Fill() { // Fill the branch basket with the referenced objects parent numbers. Int_t nbytes = TBranch::Fill(); return nbytes; } //______________________________________________________________________________ void TBranchRef::FillLeaves(TBuffer &b) { // This function called by TBranch::Fill overloads TBranch::FillLeaves. if (!fRefTable) fRefTable = new TRefTable(this,100); fRefTable->FillBuffer(b); } //______________________________________________________________________________ Bool_t TBranchRef::Notify() { // This function is called by TRefTable::Notify, itself called by // TRef::GetObject. // The function reads the branch containing the object referenced // by the TRef. if (!fRefTable) fRefTable = new TRefTable(this,100); UInt_t uid = fRefTable->GetUID(); TProcessID* context = fRefTable->GetUIDContext(); GetEntry(fReadEntry); TBranch *branch = (TBranch*)fRefTable->GetParent(uid, context); if (branch) { // don't re-read, the user might have changed some object if (branch->GetReadEntry() != fReadEntry) branch->GetEntry(fReadEntry); } else { //scan the TRefTable of possible friend Trees TList *friends = fTree->GetListOfFriends(); if (!friends) return kTRUE; TObjLink *lnk = friends->FirstLink(); while (lnk) { TFriendElement* elem = (TFriendElement*)lnk->GetObject(); TTree *tree = elem->GetTree(); TBranchRef *bref = tree->GetBranchRef(); if (bref) { bref->GetEntry(fReadEntry); branch = (TBranch*)bref->GetRefTable()->GetParent(uid, context); if (branch) { // don't re-read, the user might have changed some object if (branch->GetReadEntry() != fReadEntry) branch->GetEntry(fReadEntry); return kTRUE; } } lnk = lnk->Next(); } } return kTRUE; } //______________________________________________________________________________ void TBranchRef::Print(Option_t *option) const { // Print the TRefTable branch. TBranch::Print(option); } //______________________________________________________________________________ void TBranchRef::ReadLeaves(TBuffer &b) { // This function called by TBranch::GetEntry overloads TBranch::ReadLeaves. if (!fRefTable) fRefTable = new TRefTable(this,100); fRefTable->ReadBuffer(b); } //______________________________________________________________________________ void TBranchRef::Reset(Option_t *option) { // Existing buffers are deleted // Entries, max and min are reset // TRefTable is cleared. TBranch::Reset(option); if (!fRefTable) fRefTable = new TRefTable(this,100); fRefTable->Reset(); } //______________________________________________________________________________ void TBranchRef::SetParent(const TObject *object) { // this function is called by TBranchElement::Fill when filling // branches that may contain referenced objects. if (!fRefTable) fRefTable = new TRefTable(this,100); TRefTable::SetRefTable(fRefTable); fRefTable->SetParent(object); }