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TLeaf.h
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1 // @(#)root/tree:$Id$
2 // Author: Rene Brun 12/01/96
3 
4 /*************************************************************************
5  * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers. *
6  * All rights reserved. *
7  * *
8  * For the licensing terms see $ROOTSYS/LICENSE. *
9  * For the list of contributors see $ROOTSYS/README/CREDITS. *
10  *************************************************************************/
11 
12 #ifndef ROOT_TLeaf
13 #define ROOT_TLeaf
14 
15 
16 //////////////////////////////////////////////////////////////////////////
17 // //
18 // TLeaf //
19 // //
20 // A TTree object is a list of TBranch. //
21 // A TBranch object is a list of TLeaf. In most cases, the TBranch //
22 // will have one TLeaf. //
23 // A TLeaf describes the branch data types and holds the data. //
24 // //
25 // A few notes about the data held by the leaf. It can contain: //
26 // 1 a single object or primitive (e.g., one float), //
27 // 2 a fixed-number of objects (e.g., each entry has two floats). //
28 // The number of elements per entry is saved in `fLen`. //
29 // 3 a dynamic number of primitives. The number of objects in each //
30 // entry is saved in the `fLeafCount` branch. //
31 // //
32 // Note options (2) and (3) can combined - if fLeafCount says an entry //
33 // has 3 elements and fLen is 2, then there will be 6 objects in that //
34 // entry. //
35 // //
36 // Additionally, `fNdata` is transient and generated on read to //
37 // determine the necessary size of a buffer to hold event data; //
38 // depending on the call-site, it may be sized larger than the number //
39 // of elements //
40 // //
41 //////////////////////////////////////////////////////////////////////////
42 
43 
44 #include "TNamed.h"
45 
46 #ifdef R__LESS_INCLUDES
47 class TBranch;
48 #else
49 #include "TBranch.h"
50 #endif
51 
52 class TClonesArray;
53 class TBrowser;
54 
55 class TLeaf : public TNamed {
56 
57 private:
58 
59  virtual Int_t GetOffsetHeaderSize() const {return 0;}
60 
61 protected:
62 
63  using Counts_t = std::vector<Int_t>;
64  struct LeafCountValues {
66  Long64_t fStartEntry{-1}; ///<! entry number of corresponding to element 0 of the vector.
67  };
68 
69  Int_t fNdata; ///<! Number of elements in fAddress data buffer.
70  Int_t fLen; ///< Number of fixed length elements in the leaf's data.
71  Int_t fLenType; ///< Number of bytes for this data type
72  Int_t fOffset; ///< Offset in ClonesArray object (if one)
73  Bool_t fIsRange; ///< (=kTRUE if leaf has a range, kFALSE otherwise). This is equivalent to being a 'leafcount'. For a TLeafElement the range information is actually store in the TBranchElement.
74  Bool_t fIsUnsigned; ///< (=kTRUE if unsigned, kFALSE otherwise)
75  TLeaf *fLeafCount; ///< Pointer to Leaf count if variable length (we do not own the counter)
76  TBranch *fBranch; ///<! Pointer to supporting branch (we do not own the branch)
77  LeafCountValues *fLeafCountValues; ///<! Cache of collection/array sizes
78 
79  TLeaf(const TLeaf&);
80  TLeaf& operator=(const TLeaf&);
81 
82  template <typename T> struct GetValueHelper {
83  static T Exec(const TLeaf *leaf, Int_t i = 0) { return leaf->GetValue(i); }
84  };
85 
86  Int_t *GenerateOffsetArrayBase(Int_t base, Int_t events) const; // For leaves containing fixed-size objects (no
87  // polymorphism!), this will generate an appropriate
88  // offset array.
89 
90 
91 public:
92  enum EStatusBits {
93  kIndirectAddress = BIT(11), ///< Data member is a pointer to an array of basic types.
94  kNewValue = BIT(12) ///< Set if we own the value buffer and so must delete it ourselves.
95  };
96 
97  enum class DeserializeType {
98  kInvalid = 0, // Invalid deserialization information.
99  kDestructive, // Deserialization of this Leaf requires a separate output buffer.
100  kInPlace, // Deserialization can be done directly in the input buffer.
101  kZeroCopy, // In-memory and on-disk representation of this object are identical.
102  };
103 
104  TLeaf();
105  TLeaf(TBranch *parent, const char *name, const char *type);
106  virtual ~TLeaf();
107 
108  virtual void Browse(TBrowser *b);
109  virtual Bool_t CanGenerateOffsetArray() {return fLeafCount;} // overload and return true if this leaf can generate its own offset array.
110  virtual void Export(TClonesArray *, Int_t) {}
111  virtual void FillBasket(TBuffer &b);
112  virtual Int_t *GenerateOffsetArray(Int_t base, Int_t events) { return GenerateOffsetArrayBase(base, events); }
113  TBranch *GetBranch() const { return fBranch; }
115  /// If this leaf stores a variable-sized array or a multi-dimensional array whose last dimension has variable size,
116  /// return a pointer to the TLeaf that stores such size. Return a nullptr otherwise.
117  virtual TLeaf *GetLeafCount() const { return fLeafCount; }
118  virtual TLeaf *GetLeafCounter(Int_t &countval) const;
119 
120  virtual const Counts_t *GetLeafCountValues(Long64_t start, Long64_t len);
121 
122  virtual Int_t GetLen() const;
123  /// Return the fixed length of this leaf.
124  /// If the leaf stores a fixed-length array, this is the size of the array.
125  /// If the leaf stores a non-array or a variable-sized array, this method returns 1.
126  /// If the leaf stores an array with 2 or more dimensions, this method returns the total number of elements in the
127  /// dimensions with static length: for example for float[3][2][] it would return 6.
128  virtual Int_t GetLenStatic() const { return fLen; }
129  virtual Int_t GetLenType() const { return fLenType; }
130  virtual Int_t GetMaximum() const { return 0; }
131  virtual Int_t GetMinimum() const { return 0; }
132  virtual Int_t GetNdata() const { return fNdata; }
133  virtual Int_t GetOffset() const { return fOffset; }
134  virtual void *GetValuePointer() const { return 0; }
135  virtual const char *GetTypeName() const { return ""; }
136 
137  virtual Double_t GetValue(Int_t i = 0) const;
138  virtual Long64_t GetValueLong64(Int_t i = 0) const { return GetValue(i); } // overload only when it matters.
139  virtual LongDouble_t GetValueLongDouble(Int_t i = 0) const { return GetValue(i); } // overload only when it matters.
140  template <typename T> T GetTypedValue(Int_t i = 0) const { return GetValueHelper<T>::Exec(this, i); }
141 
142  virtual Bool_t IncludeRange(TLeaf *) { return kFALSE; } // overload to copy/set fMinimum and fMaximum to include/be wide than those of the parameter
143  virtual void Import(TClonesArray *, Int_t) {}
144  virtual Bool_t IsOnTerminalBranch() const { return kTRUE; }
145  virtual Bool_t IsRange() const { return fIsRange; }
146  virtual Bool_t IsUnsigned() const { return fIsUnsigned; }
147  virtual void PrintValue(Int_t i = 0) const;
148  virtual void ReadBasket(TBuffer &) {}
150  virtual bool ReadBasketFast(TBuffer&, Long64_t) { return false; } // Read contents of leaf into a user-provided buffer.
151  virtual bool ReadBasketSerialized(TBuffer&, Long64_t) { return false; } // Read contents of leaf into a user-provided buffer
152  virtual void ReadValue(std::istream & /*s*/, Char_t /*delim*/ = ' ') {
153  Error("ReadValue", "Not implemented!");
154  }
155  Int_t ResetAddress(void *add, Bool_t destructor = kFALSE);
156  virtual void SetAddress(void *add = 0);
157  virtual void SetBranch(TBranch *branch) { fBranch = branch; }
158  virtual void SetLeafCount(TLeaf *leaf);
159  virtual void SetLen(Int_t len = 1) { fLen = len; }
160  virtual void SetOffset(Int_t offset = 0) { fOffset = offset; }
161  virtual void SetRange(Bool_t range = kTRUE) { fIsRange = range; }
162  virtual void SetUnsigned() { fIsUnsigned = kTRUE; }
163 
164  ClassDef(TLeaf, 2); // Leaf: description of a Branch data type
165 };
166 
167 
168 template <> struct TLeaf::GetValueHelper<Long64_t> {
169  static Long64_t Exec(const TLeaf *leaf, Int_t i = 0) { return leaf->GetValueLong64(i); }
170 };
171 template <> struct TLeaf::GetValueHelper<ULong64_t> {
172  static ULong64_t Exec(const TLeaf *leaf, Int_t i = 0) { return (ULong64_t)leaf->GetValueLong64(i); }
173 };
174 template <> struct TLeaf::GetValueHelper<LongDouble_t> {
175  static LongDouble_t Exec(const TLeaf *leaf, Int_t i = 0) { return leaf->GetValueLongDouble(i); }
176 };
177 
178 
179 inline Double_t TLeaf::GetValue(Int_t /*i = 0*/) const { return 0.0; }
180 inline void TLeaf::PrintValue(Int_t /* i = 0*/) const {}
181 inline void TLeaf::SetAddress(void* /* add = 0 */) {}
182 
183 #endif
virtual ~TLeaf()
Destructor.
Definition: TLeaf.cxx:117
A TLeaf describes individual elements of a TBranch See TBranch structure in TTree.
Definition: TLeaf.h:55
virtual Int_t * GenerateOffsetArray(Int_t base, Int_t events)
Definition: TLeaf.h:112
virtual const Counts_t * GetLeafCountValues(Long64_t start, Long64_t len)
If this branch is a branch count, return the set of collection size for the entry range requested sta...
Definition: TLeaf.cxx:328
double T(double x)
Definition: ChebyshevPol.h:34
#define BIT(n)
Definition: Rtypes.h:83
int Int_t
Definition: CPyCppyy.h:43
virtual Bool_t IsUnsigned() const
Definition: TLeaf.h:146
virtual const char * GetTypeName() const
Definition: TLeaf.h:135
virtual TLeaf * GetLeafCounter(Int_t &countval) const
Return a pointer to the counter of this leaf (if any) or store the number of elements that the leaf c...
Definition: TLeaf.cxx:213
virtual void PrintValue(Int_t i=0) const
Definition: TLeaf.h:180
Buffer base class used for serializing objects.
Definition: TBuffer.h:42
Int_t * GenerateOffsetArrayBase(Int_t base, Int_t events) const
If the class supports it, generate an offset array base.
Definition: TLeaf.cxx:165
Long64_t fStartEntry
! entry number of corresponding to element 0 of the vector.
Definition: TLeaf.h:66
virtual Int_t GetOffset() const
Definition: TLeaf.h:133
virtual Int_t GetOffsetHeaderSize() const
Definition: TLeaf.h:59
virtual void Import(TClonesArray *, Int_t)
Definition: TLeaf.h:143
bool Bool_t
Definition: RtypesCore.h:61
virtual Long64_t GetValueLong64(Int_t i=0) const
Definition: TLeaf.h:138
static Long64_t Exec(const TLeaf *leaf, Int_t i=0)
Definition: TLeaf.h:169
virtual LongDouble_t GetValueLongDouble(Int_t i=0) const
Definition: TLeaf.h:139
Int_t fLenType
Number of bytes for this data type.
Definition: TLeaf.h:71
static ULong64_t Exec(const TLeaf *leaf, Int_t i=0)
Definition: TLeaf.h:172
virtual void SetRange(Bool_t range=kTRUE)
Definition: TLeaf.h:161
std::vector< Int_t > Counts_t
Definition: TLeaf.h:63
#define ClassDef(name, id)
Definition: Rtypes.h:322
virtual Bool_t IncludeRange(TLeaf *)
Definition: TLeaf.h:142
virtual Double_t GetValue(Int_t i=0) const
Definition: TLeaf.h:179
The TNamed class is the base class for all named ROOT classes.
Definition: TNamed.h:29
virtual void SetLen(Int_t len=1)
Definition: TLeaf.h:159
Set if we own the value buffer and so must delete it ourselves.
Definition: TLeaf.h:94
virtual Bool_t IsRange() const
Definition: TLeaf.h:145
virtual bool ReadBasketFast(TBuffer &, Long64_t)
Definition: TLeaf.h:150
virtual Int_t GetLenType() const
Definition: TLeaf.h:129
Counts_t fValues
Definition: TLeaf.h:65
virtual void SetBranch(TBranch *branch)
Definition: TLeaf.h:157
virtual DeserializeType GetDeserializeType() const
Definition: TLeaf.h:114
Int_t fLen
Number of fixed length elements in the leaf&#39;s data.
Definition: TLeaf.h:70
virtual void Export(TClonesArray *, Int_t)
Definition: TLeaf.h:110
virtual void SetAddress(void *add=0)
Definition: TLeaf.h:181
virtual void FillBasket(TBuffer &b)
Pack leaf elements in Basket output buffer.
Definition: TLeaf.cxx:157
Using a TBrowser one can browse all ROOT objects.
Definition: TBrowser.h:37
virtual Int_t GetLen() const
Return the number of effective elements of this leaf, for the current entry.
Definition: TLeaf.cxx:368
virtual bool ReadBasketSerialized(TBuffer &, Long64_t)
Definition: TLeaf.h:151
Int_t fNdata
! Number of elements in fAddress data buffer.
Definition: TLeaf.h:69
static T Exec(const TLeaf *leaf, Int_t i=0)
Definition: TLeaf.h:83
LeafCountValues * fLeafCountValues
! Cache of collection/array sizes
Definition: TLeaf.h:77
virtual Bool_t CanGenerateOffsetArray()
Definition: TLeaf.h:109
long double LongDouble_t
Definition: cpp_cppyy.h:15
virtual void Error(const char *method, const char *msgfmt,...) const
Issue error message.
Definition: TObject.cxx:889
virtual TLeaf * GetLeafCount() const
If this leaf stores a variable-sized array or a multi-dimensional array whose last dimension has vari...
Definition: TLeaf.h:117
virtual void * GetValuePointer() const
Definition: TLeaf.h:134
virtual Int_t GetMinimum() const
Definition: TLeaf.h:131
virtual void SetLeafCount(TLeaf *leaf)
Set the leaf count of this leaf.
Definition: TLeaf.cxx:429
virtual Int_t GetLenStatic() const
Return the fixed length of this leaf.
Definition: TLeaf.h:128
virtual void SetOffset(Int_t offset=0)
Definition: TLeaf.h:160
static LongDouble_t Exec(const TLeaf *leaf, Int_t i=0)
Definition: TLeaf.h:175
const Bool_t kFALSE
Definition: RtypesCore.h:90
virtual Int_t GetMaximum() const
Definition: TLeaf.h:130
double Double_t
Definition: RtypesCore.h:57
Data member is a pointer to an array of basic types.
Definition: TLeaf.h:93
EStatusBits
Definition: TObject.h:57
virtual void Browse(TBrowser *b)
Browse the content of this leaf.
Definition: TLeaf.cxx:134
int type
Definition: TGX11.cxx:120
Bool_t fIsUnsigned
(=kTRUE if unsigned, kFALSE otherwise)
Definition: TLeaf.h:74
virtual void ReadBasket(TBuffer &)
Definition: TLeaf.h:148
virtual void SetUnsigned()
Definition: TLeaf.h:162
virtual void ReadBasketExport(TBuffer &, TClonesArray *, Int_t)
Definition: TLeaf.h:149
virtual void ReadValue(std::istream &, Char_t=' ')
Definition: TLeaf.h:152
Int_t fOffset
Offset in ClonesArray object (if one)
Definition: TLeaf.h:72
char Char_t
Definition: RtypesCore.h:31
An array of clone (identical) objects.
Definition: TClonesArray.h:29
Bool_t fIsRange
(=kTRUE if leaf has a range, kFALSE otherwise). This is equivalent to being a &#39;leafcount&#39;. For a TLeafElement the range information is actually store in the TBranchElement.
Definition: TLeaf.h:73
TBranch * fBranch
! Pointer to supporting branch (we do not own the branch)
Definition: TLeaf.h:76
DeserializeType
Definition: TLeaf.h:97
unsigned long long ULong64_t
Definition: cpp_cppyy.h:14
Int_t ResetAddress(void *add, Bool_t destructor=kFALSE)
Helper routine for TLeafX::SetAddress.
Definition: TLeaf.cxx:393
TLeaf * fLeafCount
Pointer to Leaf count if variable length (we do not own the counter)
Definition: TLeaf.h:75
TLeaf()
Definition: TLeaf.cxx:32
you should not use this method at all Int_t Int_t Double_t Double_t Double_t Int_t Double_t Double_t Double_t Double_t b
Definition: TRolke.cxx:630
TLeaf & operator=(const TLeaf &)
Assignment operator.
Definition: TLeaf.cxx:94
TBranch * GetBranch() const
Definition: TLeaf.h:113
A TTree is a list of TBranches.
Definition: TBranch.h:88
virtual Bool_t IsOnTerminalBranch() const
Definition: TLeaf.h:144
const Bool_t kTRUE
Definition: RtypesCore.h:89
T GetTypedValue(Int_t i=0) const
Definition: TLeaf.h:140
char name[80]
Definition: TGX11.cxx:109
virtual Int_t GetNdata() const
Definition: TLeaf.h:132
long long Long64_t
Definition: cpp_cppyy.h:13