xAOD::TObjectManager Class Reference

Manager for EDM objects created by ROOT. More...

#include <TObjectManager.h>

Inheritance diagram for xAOD::TObjectManager:

Collaboration diagram for xAOD::TObjectManager:

Public Member Functions
	TObjectManager (::TBranch *br=0, std::unique_ptr< THolder > holder=nullptr, ::Bool_t renewOnRead=kFALSE)
	Constructor, getting hold of the created objects.
	TObjectManager (const TObjectManager &parent)
	Copy constructor.
	~TObjectManager ()
	Destructor.
TObjectManager &	operator= (const TObjectManager &parent)
	Assignment operator.
::TBranch *	branch ()
	Accessor to the branch.
::TBranch **	branchPtr ()
	Pointer to the branch's pointer.
virtual::Int_t	getEntry (::Int_t getall=0) override
	Function for updating the object in memory if needed.
virtual const void *	object () const override
	Function getting a const pointer to the object being handled.
virtual void *	object () override
	Function getting a pointer to the object being handled.
virtual void	setObject (void *obj) override
	Function replacing the object being handled.
virtual::Bool_t	create () override
	Create the object for the current event.
virtual::Bool_t	isSet () const override
	Check if the object was set for the current event.
virtual void	reset () override
	Reset the object at the end of processing of an event.
const THolder *	holder () const
	Accessor to the Holder object.
THolder *	holder ()
	Accessor to the Holder object.

Private Attributes
::TBranch *	m_branch
	Pointer keeping track of the branch.
::Long64_t	m_entry
	The last entry that was loaded for this branch.
::Bool_t	m_isSet
	Was the object set for the current event?
::Bool_t	m_renewOnRead
	Should the object be recreated on each read?
std::unique_ptr< THolder >	m_holder
	Object holding onto an EDM object in memory.

Detailed Description

Manager for EDM objects created by ROOT.

This class is used when an EDM object is meant to be created by ROOT's schema evolution system, behind the scenes.

Author

Attila Krasznahorkay Attil.nosp@m.a.Kr.nosp@m.aszna.nosp@m.hork.nosp@m.ay@ce.nosp@m.rn.c.nosp@m.h

Definition at line 29 of file TObjectManager.h.

Constructor & Destructor Documentation

TObjectManager() [1/2]

xAOD::TObjectManager::TObjectManager	(	::TBranch *	br = 0,
		std::unique_ptr< THolder >	holder = nullptr,
		::Bool_t	renewOnRead = kFALSE )

Constructor, getting hold of the created objects.

Definition at line 18 of file TObjectManager.cxx.

      : IObjectManager(std::move(holder)),
        m_branch( br ), m_entry( -1 ), m_isSet( kTRUE ),
        m_renewOnRead( renewOnRead ) {
   }

TObjectManager() [2/2]

xAOD::TObjectManager::TObjectManager

(

const TObjectManager &

parent

)

Copy constructor.

Definition at line 26 of file TObjectManager.cxx.

      : IObjectManager(parent),
        m_branch( parent.m_branch ), m_entry( parent.m_entry ),
        m_isSet( parent.m_isSet ), m_renewOnRead( parent.m_renewOnRead ) {
 
   }

~TObjectManager()

xAOD::TObjectManager::~TObjectManager ( )

default

Destructor.

Member Function Documentation

branch()

TBranch * xAOD::TObjectManager::branch

(

)

Accessor to the branch.

Definition at line 51 of file TObjectManager.cxx.

                                   {
 
      return m_branch;
   }

branchPtr()

TBranch ** xAOD::TObjectManager::branchPtr

(

)

Pointer to the branch's pointer.

This sort of access to the internal TBranch object is needed when connecting to the input tree.

One has to make sure that the correct pointer is being pointed to by the input tree.

Returns

A pointer to the internal branch pointer

Definition at line 62 of file TObjectManager.cxx.

                                       {
 
      return &m_branch;
   }

create()

Bool_t xAOD::TObjectManager::create ( )

overridevirtual

Create the object for the current event.

Dummy implementation as full objects can't be missing.

Implements xAOD::TVirtualManager.

Definition at line 171 of file TObjectManager.cxx.

                                 {
 
      return m_isSet;
   }

getEntry()

Int_t xAOD::TObjectManager::getEntry ( ::Int_t getall = 0 )

overridevirtual

Function for updating the object in memory if needed.

This function is used to load the contents of a branch only when it needs to be done.

It keeps track of which entry was already loaded for a branch/object, and only asks the branch to load an entry when it really has to be done.

Returns

0 if no new entry was read, the number of read bytes otherwise

Implements xAOD::TVirtualManager.

Definition at line 74 of file TObjectManager.cxx.

                                                {
 
      // Make sure that the branch is associated to a tree
      // as the entry to be read is retrieved from the tree
      if (!m_branch->GetTree()){
         Error("xAOD::TObjectManager::getEntry",
            XAOD_MESSAGE("Branch=%s is not associated to any tree while reading of branches within this class relies on that"),
            m_branch->GetName());
         return -1;
      }
 
      // Get the entry that should be read
      // The entry to be read is set with TTree::LoadTree()
      // NB: for a branch from a friend tree and if the friend tree has an index built,
      // then the entry to read is found when calling the TTree::LoadTree() function
      // that matches the major and minor values between the main tree and the friend tree
      ::Long64_t entry = m_branch->GetTree()->GetReadEntry();
 
      if ( entry  < 0 ){
         // Raise error as it implies
         // either that the TTree::LoadTree() function has not been called
         // or
         // the entry requested to be read by the user
         // is not corresponding to any entry for the friend tree
         Error("xAOD::TObjectManager::getEntry",
            XAOD_MESSAGE( "Entry to read is not set for branch=%s from tree=%s. "
            "It is either because TTree::LoadTree(entry) was not called "
            "beforehand in the TEvent class OR "
            "the entry requested to be read for the main tree is not corresponding to an event for the friend tree" ),
            m_branch->GetName(),
            m_branch->GetTree()->GetName());
         return -1;
      }
 
      // Check if anything needs to be done:
      if( entry == m_entry ) return 0;
 
      // Make sure that the branch is not in "MakeClass mode":
      if( m_branch->GetMakeClass() ) {
         m_branch->SetMakeClass( 0 );
      }
 
      // Renew the object in memory if we are in such a mode:
      if( m_renewOnRead ) {
         holder()->renew();
      }
 
      // Load the entry.
      const ::Int_t nbytes = m_branch->GetEntry( entry, getall );
 
      // If the load was successful, remember that we loaded this entry.
      if( nbytes >= 0 ) {
         m_entry = entry;
      }
 
      // This is a tricky thing... Parts of the code try to minimise some
      // operations to only happen when an object is getting updated. But
      // it can happen that an interface or auxiliary store object doesn't
      // actually store any data itself. So TBranch::GetEntry will return 0.
      // But we still need to tell the code looking at this return value
      // that we did go to a new event. So we should never return 0 at
      // this point...
      if( nbytes ) {
         return nbytes;
      } else {
         return 1;
      }
   }

holder() [1/2]

THolder * xAOD::Details::IObjectManager::holder ( )

inherited

Accessor to the Holder object.

Definition at line 48 of file IObjectManager.cxx.

                                {
 
  return m_holder.get();
}

holder() [2/2]

const THolder * xAOD::Details::IObjectManager::holder ( ) const

inherited

Accessor to the Holder object.

Definition at line 43 of file IObjectManager.cxx.

                                            {
 
  return m_holder.get();
}

isSet()

Bool_t xAOD::TObjectManager::isSet ( ) const

overridevirtual

Check if the object was set for the current event.

Returns

kTRUE if the object for this event was set, kFALSE otherwise

Implements xAOD::TVirtualManager.

Definition at line 179 of file TObjectManager.cxx.

                                      {
 
      return m_isSet;
   }

object() [1/2]

const void * xAOD::TObjectManager::object ( ) const

overridevirtual

Function getting a const pointer to the object being handled.

This function gives an easy access to the object managed by this object.

Returns

A typeless pointer to the object being managed

Implements xAOD::TVirtualManager.

Definition at line 148 of file TObjectManager.cxx.

                                            {
 
      return holder()->get();
   }

object() [2/2]

void * xAOD::TObjectManager::object ( )

overridevirtual

Function getting a pointer to the object being handled.

Implements xAOD::TVirtualManager.

Definition at line 153 of file TObjectManager.cxx.

                                {
 
      return holder()->get();
   }

operator=()

TObjectManager & xAOD::TObjectManager::operator=

(

const TObjectManager &

parent

)

Assignment operator.

Definition at line 35 of file TObjectManager.cxx.

                                                                           {
 
      // Check if we need to do anything:
      if( this == &parent ) {
         return *this;
      }
 
      m_branch = parent.m_branch;
      IObjectManager::operator=(parent);
      m_entry       = parent.m_entry;
      m_isSet       = parent.m_isSet;
      m_renewOnRead = parent.m_renewOnRead;
 
      return *this;
   }

reset()

void xAOD::TObjectManager::reset ( )

overridevirtual

Reset the object at the end of processing of an event.

This function needs to be called after an event was filled into the output TTree.

It tells the manager object that it needs to wait for another object to be set up for the upcoming event.

Implements xAOD::TVirtualManager.

Definition at line 188 of file TObjectManager.cxx.

                              {
 
      m_isSet = kFALSE;
      return;
   }

setObject()

void xAOD::TObjectManager::setObject ( void * obj )

overridevirtual

Function replacing the object being handled.

This is just a convenient way of calling THolder::Set from TEvent.

Parameters

obj	The object to replace the previously managed one

Implements xAOD::TVirtualManager.

Definition at line 162 of file TObjectManager.cxx.

                                             {
 
      holder()->set( obj );
      m_isSet = kTRUE;
      return;
   }

Member Data Documentation

m_branch

::TBranch* xAOD::TObjectManager::m_branch

private

Pointer keeping track of the branch.

Definition at line 68 of file TObjectManager.h.

m_entry

::Long64_t xAOD::TObjectManager::m_entry

private

The last entry that was loaded for this branch.

Definition at line 70 of file TObjectManager.h.

m_holder

std::unique_ptr<THolder> xAOD::Details::IObjectManager::m_holder

privateinherited

Object holding onto an EDM object in memory.

Definition at line 44 of file IObjectManager.h.

m_isSet

::Bool_t xAOD::TObjectManager::m_isSet

private

Was the object set for the current event?

Definition at line 72 of file TObjectManager.h.

m_renewOnRead

::Bool_t xAOD::TObjectManager::m_renewOnRead

private

Should the object be recreated on each read?

Definition at line 74 of file TObjectManager.h.

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

• TObjectManager.h
• TObjectManager.cxx