class <SI-Namespace>::common::<SI>

As a common namespace, the class bundles static metadata and identifiers for an interface in Communication Management of AUTOSAR Adaptive SWS CommunicationManagement §8.2.2.1 “Public Member Variables”. It provides basic information for unique identification and versioning of the service via serviceIdentifier and serviceVersion [SWS_CM_11506]. In addition, serviceContractVersionMajor and serviceContractVersionMinor define the exact service contract version to ensure interface compatibility. Interpretation: Since all declared elements are static, the class presumably requires no instantiation at runtime and is included immutably process-wide. Question Q-bdf8084e3c4a2dec (open)

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Context

In the AUTOSAR Adaptive Platform, the C++ class <SI-Namespace>::common::<SI> in the com module (Communication Management) fulfills the central role of a common metadata and namespace container for a defined service interface SWS CommunicationManagement §8.2.2.1 “Public Member Variables”. The class combines static properties and interface identifiers that apply uniformly to both service consumers and service providers and are provided via the header file #include "<SiNamespaceDerivedDirectoryPath>/<SiShortname>_common.h" [SWS_CM_11506].

The primary interaction partners include functional Communication Management ara::com, whose fundamental data types are included. The class exposes the service identifier serviceIdentifier of type const ara::com::ServiceIdentifierType [SWS_CM_11506] (SWS CommunicationManagement §8.2.2.1.3 “serviceIdentifier”) as well as the service version serviceVersion of type const ara::com::ServiceVersionType [SWS_CM_11507] (SWS CommunicationManagement §8.2.2.1.4 “serviceVersion”). Interpretation: Application and platform components use this common class definition as an authoritative reference to set up service instances via uniform identifiers and interface contracts. Question (open)

Context diagram: Classification of the common interface class in interaction with service applications and basic types of Communication Management. Sources: [SWS_CM_11506], [SWS_CM_11507], SWS CommunicationManagement §8.2.2.1 “Public Member Variables”.

Lifecycle

With regard to lifecycle, <SI-Namespace>::common::<SI> differs fundamentally from dynamic instance classes: It requires no explicit instantiation and possesses no dynamically managed state. All interface variables defined in the specification are declared as static class members SWS CommunicationManagement §8.2.2.1 “Public Member Variables”.

The identifier serviceIdentifier [SWS_CM_11506] and versioning serviceVersion [SWS_CM_11507] are declared as static const. In addition, serviceContractVersionMajor [SWS_CM_11508] (SWS CommunicationManagement §8.2.2.1.1 “serviceContractVersionMajor”) and serviceContractVersionMinor [SWS_CM_11509] (SWS CommunicationManagement §8.2.2.1.2 “serviceContractVersionMinor”) define the contract version numbers as static std::uint32_t values. Interpretation: The static lifetime of these symbols corresponds to the entire process duration; their initialization is likely performed when loading the respective module or shared library. Question (open) There is no dynamic destruction or deallocation of memory resources.

Regarding concurrency, variables serviceIdentifier and serviceVersion qualified with const provide unrestricted thread safety for simultaneous read accesses. Interpretation: Because version variables serviceContractVersionMajor and serviceContractVersionMinor represent contractual specification states, they presumably remain unchanged at runtime, which allows simultaneous read accesses from multiple execution threads without synchronization overhead. Question Q-2335ea4535e239d6 (open)

Usage Path

The typical usage path comprises static access to metadata and version information to ensure interface compatibility:

• Header inclusion: The application or the generated communication layer includes file <SiNamespaceDerivedDirectoryPath>/<SiShortname>_common.h to obtain access to namespace <SI-Namespace>::common::<SI> [SWS_CM_11506].
• Service identification: Components access the unique identifier of the service directly via <SI-Namespace>::common::<SI>::serviceIdentifier, for example to initialize instances or to register with the communication infrastructure [SWS_CM_11506] (SWS CommunicationManagement §8.2.2.1.3 “serviceIdentifier”).
• Version comparison: To verify interface compatibility between communication partners, serviceVersion [SWS_CM_11507] as well as contract versions serviceContractVersionMajor [SWS_CM_11508] and serviceContractVersionMinor [SWS_CM_11509] are read.

Preconditions for read access do not exist, as all constants are already available at program start. Error states or exceptions are not specified for pure read access to these static variables.