a smart pointer to an object of a given type in an IProxyDict (such as StoreGateSvc). It d-casts and caches locally the pointed-at object, to speed-up subsequent accesses. It can be reset by the store for asynchronous updates (IOVSvc) More...

#include <ReadHandle.h>

Inheritance diagram for ReadHandle< T >:

Collaboration diagram for ReadHandle< T >:

Detailed Description

a smart pointer to an object of a given type in an IProxyDict (such as StoreGateSvc). It d-casts and caches locally the pointed-at object, to speed-up subsequent accesses. It can be reset by the store for asynchronous updates (IOVSvc)

SG::ReadHandle<T> can access const and non-const proxies in StoreGate but cannot modify them (i.e.: it is actually a const T*). A valid proxy must already exist in StoreGate.

Usage example:

class MyAlg : public AthAlgorithm
{
  SG::ReadHandle<int> m_int;
};
 
MyAlg::MyAlg(...) : ..., m_int("MyIntSgKey") {
   declareProperty("IntHandle",
                   m_int = SG::ReadHandle<int>("MyIntSgKey"),
                   "a handle to an int in StoreGate");
}
 
StatusCode MyAlg::execute()
{
  ATH_MSG_INFO("int value @[" << m_int.name() << "]="
               << *m_int);
  return StatusCode::SUCCESS;
}

For more information have a look under the package Control/AthenaExamples/AthExHelloWorld

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

StoreGate/StoreGate/ReadHandle.h