class ara::exec::FunctionGroupState

The class ara::exec::FunctionGroupState represents a function group state defined in the AUTOSAR metamodel and binds it across its entire lifetime to a specific function group and the associated ARXML path [SWS_EM_02324]. Instances are created with the short-name of the target declaration, support full copy and move semantics, and enable the direct equivalence comparison of model states [SWS_EM_02273]. All operations are defined as exception-safe as well as noexcept, whereby modifying assignments and destructions, unlike thread-safe comparisons, must not be executed concurrently without synchronization.

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Context

The class ara::exec::FunctionGroupState represents a function group state defined in the AUTOSAR metamodel (ARXML). Within module exec of the Adaptive Platform, an instance of this class serves as an implementation-specific representation of the corresponding metamodel information. A state is always bound to a concrete function group, which is referenced via an instance of FunctionGroup, and identified as a string via the short-name of the associated ModeDeclaration [SWS_EM_02324]. Via equality and inequality operators, instances can be compared directly with one another to determine whether they represent the same metamodel element [SWS_EM_02273] [SWS_EM_02274].

Context diagram: Integration of FunctionGroupState between function group and ARXML metamodel. Sources: [SWS_EM_02324], [SWS_EM_02273].

Lifecycle

An instance is created via the parameterized constructor, which takes a reference to the associated FunctionGroup and a ara::core::StringView with the name of the ModeDeclaration [SWS_EM_02324]. After creation, the internal value of the object remains firmly bound to the underlying ARXML path across its entire lifetime. The class supports complete value semantics:

• Copying: A copy constructor [SWS_EM_02325] and a copy assignment operator [SWS_EM_02330] enable duplicating instances.
• Moving: Resources can be efficiently transferred to new or existing instances via the move constructor [SWS_EM_02331] and the move assignment operator [SWS_EM_02332].
• Destruction: The destructor properly releases the resources of the instance [SWS_EM_02272].

Regarding concurrency, creating an instance via the constructor is thread-safe [SWS_EM_02324]. The comparison operations are also thread-safe [SWS_EM_02273] [SWS_EM_02274]. In contrast, all modifying lifecycle operations—including copy constructor [SWS_EM_02325], move constructor [SWS_EM_02331], copy assignment [SWS_EM_02330], move assignment [SWS_EM_02332], and destructor [SWS_EM_02272]—are declared as not thread-safe.

Usage Path

A typical usage path comprises the creation, forwarding, evaluation, and destruction of a state representation:

1. Instantiation: The application creates a FunctionGroupState object specifying the target function group and the name of the ModeDeclaration [SWS_EM_02324].
2. Forwarding or assignment: If needed, the object can be forwarded via copy [SWS_EM_02325] or move [SWS_EM_02331] or assigned to existing variables [SWS_EM_02330] [SWS_EM_02332].
3. State comparison: At runtime, the instance is compared with another instance to check whether both represent the same metamodel element [SWS_EM_02273] or differ from each other [SWS_EM_02274].
4. Release: Upon leaving the scope, the instance is destroyed via the destructor [SWS_EM_02272].

Error Scenarios

All methods of the class are declared with noexcept and specified as exception-safe [SWS_EM_02324] [SWS_EM_02325] [SWS_EM_02331] [SWS_EM_02330] [SWS_EM_02332] [SWS_EM_02273] [SWS_EM_02274] [SWS_EM_02272]. Neither are C++ exceptions thrown nor are error codes returned via return types such as ara::core::Result.

A precondition for error-free creation is the presence of a valid FunctionGroup as well as a ModeDeclaration defined in the metamodel [SWS_EM_02324]. Interpretation: Since constructor [SWS_EM_02324] returns no error objects and throws no exceptions, passing non-existent metamodel names is unlikely to be intercepted via regular API error codes, but presumably requires a correctly configured system model prior to instantiation. Question Q-7926777bafd2a76e (open)

Another failure scenario concerns uncoordinated concurrency: If copy, move, or destruction operations are executed concurrently on the same instance without external synchronization, race conditions threaten because these interfaces are not thread-safe [SWS_EM_02325] [SWS_EM_02330] [SWS_EM_02331] [SWS_EM_02332] [SWS_EM_02272].