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ROOT::Experimental::RFieldZero Class Reference

The container field for an ntuple model, which itself has no physical representation.

Definition at line 321 of file RField.hxx.

Public Member Functions

 RFieldZero ()
 
void AcceptVisitor (Detail::RFieldVisitor &visitor) const final
 
Detail::RFieldValue CaptureValue (void *) final
 Creates a value from a memory location with an already constructed object.
 
void GenerateColumnsImpl () final
 Creates the backing columns corresponsing to the field type for writing.
 
void GenerateColumnsImpl (const RNTupleDescriptor &) final
 Creates the backing columns corresponsing to the field type for reading.
 
Detail::RFieldValue GenerateValue (void *) override
 Generates a tree value in a given location of size at least GetValueSize().
 
size_t GetValueSize () const final
 The number of bytes taken by a value of the appropriate type.
 
- Public Member Functions inherited from ROOT::Experimental::Detail::RFieldBase
 RFieldBase (const RFieldBase &)=delete
 
 RFieldBase (RFieldBase &&)=default
 
 RFieldBase (std::string_view name, std::string_view type, ENTupleStructure structure, bool isSimple, std::size_t nRepetitions=0)
 The constructor creates the underlying column objects and connects them to either a sink or a source.
 
virtual ~RFieldBase ()
 
std::size_t Append (const RFieldValue &value)
 Write the given value into columns.
 
void Attach (std::unique_ptr< Detail::RFieldBase > child)
 Add a new subfield to the list of nested fields.
 
RSchemaIterator begin ()
 
std::unique_ptr< RFieldBaseClone (std::string_view newName) const
 Copies the field and its sub fields using a possibly new name and a new, unconnected set of columns.
 
virtual void CommitCluster ()
 Perform housekeeping tasks for global to cluster-local index translation.
 
void ConnectPageSink (RPageSink &pageSink)
 Fields and their columns live in the void until connected to a physical page storage.
 
void ConnectPageSource (RPageSource &pageSource)
 
virtual void DestroyValue (const RFieldValue &value, bool dtorOnly=false)
 Releases the resources acquired during GenerateValue (memory and constructor) This implementation works for simple types but needs to be overwritten for complex ones.
 
RSchemaIterator end ()
 
void Flush () const
 Ensure that all received items are written from page buffers to the storage.
 
RFieldValue GenerateValue ()
 Generates an object of the field type and allocates new initialized memory according to the type.
 
virtual size_t GetAlignment () const
 For many types, the alignment requirement is equal to the size; otherwise override.
 
std::string GetDescription () const
 Get the field's description.
 
virtual std::uint32_t GetFieldVersion () const
 Indicates an evolution of the mapping scheme from C++ type to columns.
 
std::string GetName () const
 
NTupleSize_t GetNElements () const
 
std::size_t GetNRepetitions () const
 
DescriptorId_t GetOnDiskId () const
 
RFieldBaseGetParent () const
 
ENTupleStructure GetStructure () const
 
std::vector< RFieldBase * > GetSubFields () const
 
int GetTraits () const
 
std::string GetType () const
 
virtual std::uint32_t GetTypeVersion () const
 Indicates an evolution of the C++ type itself.
 
bool HasReadCallbacks () const
 
bool IsSimple () const
 
RFieldBaseoperator= (const RFieldBase &)=delete
 
RFieldBaseoperator= (RFieldBase &&)=default
 
void Read (const RClusterIndex &clusterIndex, RFieldValue *value)
 
void Read (NTupleSize_t globalIndex, RFieldValue *value)
 Populate a single value with data from the tree, which needs to be of the fitting type.
 
void SetDescription (std::string_view description)
 
void SetOnDiskId (DescriptorId_t id)
 
virtual std::vector< RFieldValueSplitValue (const RFieldValue &value) const
 Creates the list of direct child values given a value for this field.
 

Protected Member Functions

std::unique_ptr< Detail::RFieldBaseCloneImpl (std::string_view newName) const override
 Called by Clone(), which additionally copies the on-disk ID.
 
- Protected Member Functions inherited from ROOT::Experimental::Detail::RFieldBase
size_t AddReadCallback (ReadCallback_t func)
 Set a user-defined function to be called after reading a value, giving a chance to inspect and/or modify the value object.
 
virtual std::size_t AppendImpl (const RFieldValue &value)
 Operations on values of complex types, e.g.
 
ROOT::Experimental::EColumnType EnsureColumnType (const std::vector< EColumnType > &requestedTypes, unsigned int columnIndex, const RNTupleDescriptor &desc)
 Throws an exception if the column given by fOnDiskId and the columnIndex in the provided descriptor is not of one of the requested types.
 
virtual void ReadGlobalImpl (NTupleSize_t globalIndex, RFieldValue *value)
 
virtual void ReadInClusterImpl (const RClusterIndex &clusterIndex, RFieldValue *value)
 
void RemoveReadCallback (size_t idx)
 

Additional Inherited Members

- Static Public Member Functions inherited from ROOT::Experimental::Detail::RFieldBase
static RResult< std::unique_ptr< RFieldBase > > Create (const std::string &fieldName, const std::string &typeName)
 Factory method to resurrect a field from the stored on-disk type information.
 
static RResult< void > EnsureValidFieldName (std::string_view fieldName)
 Check whether a given string is a valid field name.
 
- Static Public Attributes inherited from ROOT::Experimental::Detail::RFieldBase
static constexpr int kTraitMappable = 0x04
 A field of a fundamental type that can be directly mapped via RField<T>::Map(), i.e.
 
static constexpr int kTraitTriviallyConstructible = 0x01
 No constructor needs to be called, i.e.
 
static constexpr int kTraitTriviallyDestructible = 0x02
 The type is cleaned up just by freeing its memory. I.e. DestroyValue() is a no-op.
 
static constexpr int kTraitTrivialType = kTraitTriviallyConstructible | kTraitTriviallyDestructible
 Shorthand for types that are both trivially constructible and destructible.
 
- Protected Attributes inherited from ROOT::Experimental::Detail::RFieldBase
std::vector< std::unique_ptr< RColumn > > fColumns
 The columns are connected either to a sink or to a source (not to both); they are owned by the field.
 
RFieldBasefParent
 Sub fields point to their mother field.
 
RColumnfPrincipalColumn
 Points into fColumns.
 
std::vector< ReadCallback_tfReadCallbacks
 List of functions to be called after reading a value.
 
std::vector< std::unique_ptr< RFieldBase > > fSubFields
 Collections and classes own sub fields.
 
int fTraits = 0
 Properties of the type that allow for optimizations of collections of that type.
 

#include <ROOT/RField.hxx>

Inheritance diagram for ROOT::Experimental::RFieldZero:
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Constructor & Destructor Documentation

◆ RFieldZero()

ROOT::Experimental::RFieldZero::RFieldZero ( )
inline

Definition at line 326 of file RField.hxx.

Member Function Documentation

◆ AcceptVisitor()

void ROOT::Experimental::RFieldZero::AcceptVisitor ( Detail::RFieldVisitor visitor) const
finalvirtual

Reimplemented from ROOT::Experimental::Detail::RFieldBase.

Definition at line 503 of file RField.cxx.

◆ CaptureValue()

Detail::RFieldValue ROOT::Experimental::RFieldZero::CaptureValue ( void *  where)
inlinefinalvirtual

Creates a value from a memory location with an already constructed object.

Implements ROOT::Experimental::Detail::RFieldBase.

Definition at line 332 of file RField.hxx.

◆ CloneImpl()

std::unique_ptr< ROOT::Experimental::Detail::RFieldBase > ROOT::Experimental::RFieldZero::CloneImpl ( std::string_view  newName) const
overrideprotectedvirtual

Called by Clone(), which additionally copies the on-disk ID.

Implements ROOT::Experimental::Detail::RFieldBase.

Definition at line 494 of file RField.cxx.

◆ GenerateColumnsImpl() [1/2]

void ROOT::Experimental::RFieldZero::GenerateColumnsImpl ( )
inlinefinalvirtual

Creates the backing columns corresponsing to the field type for writing.

Implements ROOT::Experimental::Detail::RFieldBase.

Definition at line 328 of file RField.hxx.

◆ GenerateColumnsImpl() [2/2]

void ROOT::Experimental::RFieldZero::GenerateColumnsImpl ( const RNTupleDescriptor desc)
inlinefinalvirtual

Creates the backing columns corresponsing to the field type for reading.

The method should to check, using the page source and fOnDiskId, if the column types match and throw if they don't.

Implements ROOT::Experimental::Detail::RFieldBase.

Definition at line 329 of file RField.hxx.

◆ GenerateValue()

Detail::RFieldValue ROOT::Experimental::RFieldZero::GenerateValue ( void *  where)
inlineoverridevirtual

Generates a tree value in a given location of size at least GetValueSize().

Assumes that where has been allocated by malloc().

Implements ROOT::Experimental::Detail::RFieldBase.

Definition at line 331 of file RField.hxx.

◆ GetValueSize()

size_t ROOT::Experimental::RFieldZero::GetValueSize ( ) const
inlinefinalvirtual

The number of bytes taken by a value of the appropriate type.

Implements ROOT::Experimental::Detail::RFieldBase.

Definition at line 333 of file RField.hxx.

Libraries for ROOT::Experimental::RFieldZero:

The documentation for this class was generated from the following files: