TBranch

class TBranch : public TNamed, public TAttFill

    protected:

      void SetSkipZip(Bool_t skip = kTRUE)
      void WriteBasket(TBasket* basket)

    public:

                          TBranch()
                          TBranch(const char* name, void* address, const char* leaflist, Int_t basketsize = 32000, Int_t compress = -1)
                  virtual ~TBranch()
             virtual void Browse(TBrowser* b)
           static TClass* Class()
             virtual void DropBaskets(Option_t* option = "")
            virtual Int_t Fill()
             virtual void FillLeaves(TBuffer& b)
         virtual TBranch* FindBranch(const char* name)
           virtual TLeaf* FindLeaf(const char* name)
            virtual char* GetAddress() const
                 TBasket* GetBasket(Int_t basket)
                   Int_t* GetBasketBytes() const
                Long64_t* GetBasketEntry() const
         virtual Long64_t GetBasketSeek(Int_t basket) const
            virtual Int_t GetBasketSize() const
           virtual TList* GetBrowsables()
      virtual const char* GetClassName() const
            virtual Int_t GetCompressionLevel() const
              TDirectory* GetDirectory() const
                 Long64_t GetEntries() const
            virtual Int_t GetEntry(Long64_t entry = 0, Int_t getall = 0)
            virtual Int_t GetEntryExport(Long64_t entry, Int_t getall, TClonesArray* list, Int_t n)
                 Long64_t GetEntryNumber() const
                    Int_t GetEntryOffsetLen() const
                    Int_t GetEvent(Long64_t entry = 0)
           virtual TFile* GetFile(Int_t mode = 0)
              const char* GetFileName() const
      virtual const char* GetIconName() const
           virtual TLeaf* GetLeaf(const char* name) const
               TObjArray* GetListOfBaskets()
               TObjArray* GetListOfBranches()
               TObjArray* GetListOfLeaves()
                    Int_t GetMaxBaskets() const
                 TBranch* GetMother() const
                    Int_t GetNleaves() const
                    Int_t GetOffset() const
                    Int_t GetReadBasket() const
                 Long64_t GetReadEntry() const
            virtual Int_t GetRow(Int_t row)
                    Int_t GetSplitLevel() const
                 TBranch* GetSubBranch(const TBranch* br) const
                 Long64_t GetTotalSize() const
                 Long64_t GetTotBytes() const
                   TTree* GetTree() const
                    Int_t GetWriteBasket() const
                 Long64_t GetZipBytes() const
          virtual TClass* IsA() const
                   Bool_t IsAutoDelete() const
           virtual Bool_t IsFolder() const
             virtual void KeepCircular(Long64_t maxEntries)
            virtual Int_t LoadBaskets()
             virtual void Print(Option_t* option = "") const
             virtual void ReadBasket(TBuffer& b)
             virtual void ReadLeaves(TBuffer& b)
             virtual void Refresh(TBranch* b)
             virtual void Reset(Option_t* option = "")
             virtual void ResetAddress()
              static void ResetCount()
             virtual void ResetReadEntry()
             virtual void SetAddress(void* add)
             virtual void SetAutoDelete(Bool_t autodel = kTRUE)
             virtual void SetBasketSize(Int_t buffsize)
             virtual void SetBufferAddress(TBuffer* entryBuffer)
             virtual void SetCompressionLevel(Int_t level = 1)
             virtual void SetEntries(Long64_t entries)
             virtual void SetEntryOffsetLen(Int_t len)
             virtual void SetFile(TFile* file = 0)
             virtual void SetFile(const char* filename)
             virtual void SetOffset(Int_t offset = 0)
             virtual void SetTree(TTree* tree)
             virtual void ShowMembers(TMemberInspector& insp, char* parent)
             virtual void Streamer(TBuffer& b)
                     void StreamerNVirtual(TBuffer& b)
             virtual void UpdateAddress()

Data Members

    protected:

      static Int_t fgCount          ! branch counter
             Int_t fCompress        (=1 branch is compressed, 0 otherwise)
             Int_t fBasketSize      Initial Size of  Basket Buffer
             Int_t fEntryOffsetLen  Initial Length of fEntryOffset table in the basket buffers
             Int_t fWriteBasket     Last basket number written
          Long64_t fEntryNumber     Current entry number (last one filled in this branch)
             Int_t fOffset          Offset of this branch
             Int_t fMaxBaskets      Maximum number of Baskets so far
             Int_t fSplitLevel      Branch split level
             Int_t fNleaves         ! Number of leaves
             Int_t fReadBasket      ! Current basket number when reading
          Long64_t fReadEntry       ! Current entry number when reading
          Long64_t fEntries         Number of entries
          Long64_t fTotBytes        Total number of bytes in all leaves before compression
          Long64_t fZipBytes        Total number of bytes in all leaves after compression
         TObjArray fBranches        -> List of Branches of this branch
         TObjArray fLeaves          -> List of leaves of this branch
         TObjArray fBaskets         -> List of baskets of this branch
             Int_t fNBasketRAM      ! Number of baskets in fBasketRAM
            Int_t* fBasketRAM       ! [fNBasketRAM] table of basket numbers in memory
            Int_t* fBasketBytes     [fMaxBaskets] Lenght of baskets on file
         Long64_t* fBasketEntry     [fMaxBaskets] Table of first entry in eack basket
         Long64_t* fBasketSeek      [fMaxBaskets] Addresses of baskets on file
            TTree* fTree            ! Pointer to Tree header
             char* fAddress         ! Address of 1st leaf (variable or object)
       TDirectory* fDirectory       ! Pointer to directory where this branch buffers are stored
           TString fFileName        Name of file where buffers are stored ("" if in same file as Tree header)
          TBuffer* fEntryBuffer     ! Buffer used to directly pass the content without streaming
            TList* fBrowsables      ! List of TVirtualBranchBrowsables used for Browse()
            Bool_t fSkipZip         !After being read, the buffer will not be unziped.

    public:

      static const enum TBranch:: kAutoDelete  

Class Description

                                                                      
 A TTree is a list of TBranches                                       //                                                                      
                                                                      
 A TBranch supports:                                                  
   - The list of TLeaf describing this branch.                        
   - The list of TBasket (branch buffers).                            
                                                                      
       See TBranch structure in TTree.                                
                                                                      
 See also specialized branches:                                       
     TBranchObject in case the branch is one object                   
     TBranchClones in case the branch is an array of clone objects    

*-*-*-*-*-*Default constructor for Branch*-*-*-*-*-*-*-*-*-*
*-*        ===================================

*-*-*-*-*-*-*-*-*-*-*-*-*Create a Branch*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
*-*                =====================

       * address is the address of the first item of a structure
         or the address of a pointer to an object (see example).
       * leaflist is the concatenation of all the variable names and types
         separated by a colon character :
         The variable name and the variable type are separated by a slash (/).
         The variable type may be 0,1 or 2 characters. If no type is given,
         the type of the variable is assumed to be the same as the previous
         variable. If the first variable does not have a type, it is assumed
         of type F by default. The list of currently supported types is given below:
            - C : a character string terminated by the 0 character
            - B : an 8 bit signed integer (Char_t)
            - b : an 8 bit unsigned integer (UChar_t)
            - S : a 16 bit signed integer (Short_t)
            - s : a 16 bit unsigned integer (UShort_t)
            - I : a 32 bit signed integer (Int_t)
            - i : a 32 bit unsigned integer (UInt_t)
            - F : a 32 bit floating point (Float_t)
            - D : a 64 bit floating point (Double_t)
            - L : a 64 bit signed integer (Long64_t)
            - l : a 64 bit unsigned integer (ULong64_t)

         By default, a variable will be copied to the buffer with the number of
         bytes specified in the type descriptor character. However, if the type
         consists of 2 characters, the second character is an integer that
         specifies the number of bytes to be used when copying the variable
         to the output buffer. Example:
             X         ; variable X, type Float_t
             Y/I       : variable Y, type Int_t
             Y/I2      ; variable Y, type Int_t converted to a 16 bits integer

   See an example of a Branch definition in the TTree constructor.

   Note that in case the data type is an object, this branch can contain
   only this object.

    Note that this function is invoked by TTree::Branch

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

*-*-*-*-*-*Default destructor for a Branch*-*-*-*-*-*-*-*-*-*-*-*
*-*        ===============================

 Browser interface.

 Loop on all branch baskets. Drop all except readbasket.
 If the option contains "all", drop all baskets including
 read- and write-baskets.

*-*-*-*-*-*-*-*Loop on all leaves of this branch to fill Basket buffer*-*-*
*-*            =======================================================

 The function returns the number of bytes committed to the memory basket.
 If a write error occurs, the number of bytes returned is -1.
 If no data are written, because e.g. the branch is disabled,
 the number of bytes returned is 0.

*-*-*-*-*Return pointer to basket basketnumber in this Branch*-*-*-*-*-*
*-*      ====================================================

*-*-*-*-*Return address of basket in the file*-*-*-*-*-*
*-*      ====================================

 Returns (and, if 0, creates) browsable objects for this branch
 See TVirtualBranchBrowsable::FillListOfBrowsables.

 Return icon name depending on type of branch.

*-*-*-*-*-*Read all leaves of entry and return total number of bytes*-*-*
*-*        =========================================================
 The input argument entry is the entry serial number in the current tree.
 In case of a TChain, the entry number in the current Tree must be found
  before calling this function. example with TChain *chain;
  Long64_t localEntry = chain->LoadTree(entry);
  branch->GetEntry(localEntry);

  The function returns the number of bytes read from the input buffer.
  If entry does not exist  the function returns 0.
  If an I/O error occurs,  the function returns -1.

  See IMPORTANT REMARKS in TTree::GetEntry

*-*-*-*-*-*Read all leaves of entry and return total number of bytes*-*-*
*-* export buffers to real objects in the TClonesArray list.
*-*

 Return pointer to the file where branch buffers reside, returns 0
 in case branch buffers reside in the same file as tree header.
 If mode is 1 the branch buffer file is recreated.

*-*-*-*-*-*Return pointer to the 1st Leaf named name in thisBranch-*-*-*-*-*
*-*        =======================================================

*-*-*-*-*Return all elements of one row unpacked in internal array fValues*-*
*-*      =================================================================

 Get top level branch parent of this branch
 A top level branch has its fID negative.

 recursively find branch br in the list of branches of this branch.
 return null if br is not in this branch hierarchy.

 Return total number of bytes in the branch (including current buffer)
 =====================================================================

*-*-*-*-*Return TRUE if an existing object in a TBranchObject must be deleted
*-*      ==================================================

*-*-*-*-*Return TRUE if more than one leaf or browsables, FALSE otherwise*-*
*-*      ================================================================

 keep a maximum of fMaxEntries in memory

  Baskets associated to this branch are forced to be in memory.
  You can call TTree::SetMaxVirtualSize(maxmemory) to instruct
  the system that the total size of the imported baskets does not
  exceed maxmemory bytes.
  The function returns the number of baskets that have been put in memory.
  This method may be called to force all baskets of one or more branches
  in memory when random access to entries in this branch is required.
  See also TTree::LoadBaskets to load all baskets of all branches in memory.

*-*-*-*-*-*-*-*-*-*-*-*Print TBranch parameters*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
*-*                    ========================

*-*-*-*-*-*-*-*Loop on all leaves of this branch to read Basket buffer*-*-*
*-*            =======================================================

  refresh this branch using new information in b
  This function is called by TTree::Refresh

*-*-*-*-*-*-*-*Reset a Branch*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
*-*            ====================

    Existing buffers are deleted
    Entries, max and min are reset

*-*-*-*-*-*-*-*Reset the address of the branch*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
*-*            ===============================

*-*-*-*-*-*-*-*Set address of this branch*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
*-*            ====================

*-*-*-*-*-*-*-*Set the AutoDelete bit
*-*            ====================
 this bit is used by TBranchObject::ReadBasket to decide if an object
 referenced by a TBranchObject must be deleted or not before reading
 a new entry
 if autodel is kTRUE, this existing object will be deleted, a new object
    created by the default constructor, then object->Streamer
 if autodel is kFALSE, the existing object is not deleted. Root assumes
    that the user is taking care of deleting any internal object or array
    This can be done in Streamer itself.

 Set the basket size
 The function makes sure that the basket size is greater than fEntryOffsetlen

 Set address of this branch directly from a TBuffer to avoid streaming.

*-*-*-*-*-*-*-*Set the branch/subbranches compression level
*-*            ============================================

 Set file where this branch writes/reads its buffers.
 By default the branch buffers reside in the file where the
 Tree was created.
 If the file name where the tree was created is an absolute
 path name or an URL (e.g. /castor/... or root://host/...)
 and if the fname is not an absolute path name or an URL then
 the path of the tree file is prepended to fname to make the
 branch file relative to the tree file. In this case one can
 move the tree + all branch files to a different location in
 the file system and still access the branch files.
 The ROOT file will be connected only when necessary.
 If called by TBranch::Fill (via TBasket::WriteFile), the file
 will be created with the option "recreate".
 If called by TBranch::GetEntry (via TBranch::GetBasket), the file
 will be opened in read mode.
 To open a file in "update" mode or with a certain compression
 level, use TBranch::SetFile(TFile *file).

 Set file where this branch writes/reads its buffers.
 By default the branch buffers reside in the file where the
 Tree was created.
 If the file name where the tree was created is an absolute
 path name or an URL (e.g. /castor/... or root://host/...)
 and if the fname is not an absolute path name or an URL then
 the path of the tree file is prepended to fname to make the
 branch file relative to the tree file. In this case one can
 move the tree + all branch files to a different location in
 the file system and still access the branch files.
 The ROOT file will be connected only when necessary.
 If called by TBranch::Fill (via TBasket::WriteFile), the file
 will be created with the option "recreate".
 If called by TBranch::GetEntry (via TBranch::GetBasket), the file
 will be opened in read mode.
 To open a file in "update" mode or with a certain compression
 level, use TBranch::SetFile(TFile *file).

*-*-*-*-*-*-*-*-*Stream a class object*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
*-*              =========================================

*-*-*-*-*-*-*-*-*Write the current basket to disk*-*-*-*-*
*-*              =========================================

Inline Functions

               void SetSkipZip(Bool_t skip = kTRUE)
              char* GetAddress() const
              Int_t GetBasketSize() const
        const char* GetClassName() const
              Int_t GetCompressionLevel() const
              Int_t GetEvent(Long64_t entry = 0)
              Int_t GetEntryOffsetLen() const
             Int_t* GetBasketBytes() const
          Long64_t* GetBasketEntry() const
        TDirectory* GetDirectory() const
        const char* GetFileName() const
              Int_t GetOffset() const
              Int_t GetReadBasket() const
           Long64_t GetReadEntry() const
              Int_t GetWriteBasket() const
           Long64_t GetTotBytes() const
           Long64_t GetZipBytes() const
           Long64_t GetEntryNumber() const
         TObjArray* GetListOfBaskets()
         TObjArray* GetListOfBranches()
         TObjArray* GetListOfLeaves()
              Int_t GetMaxBaskets() const
              Int_t GetNleaves() const
              Int_t GetSplitLevel() const
           Long64_t GetEntries() const
             TTree* GetTree() const
               void ResetReadEntry()
               void SetEntryOffsetLen(Int_t len)
               void SetOffset(Int_t offset = 0)
               void SetTree(TTree* tree)
               void UpdateAddress()
               void ResetCount()
            TClass* Class()
            TClass* IsA() const
               void ShowMembers(TMemberInspector& insp, char* parent)
               void StreamerNVirtual(TBuffer& b)