class ara::diag::DiagnosticSovdArrayContentElementDataConstIterator

The class ara::diag::DiagnosticSovdArrayContentElementDataConstIterator provides a read-only forward iterator for array elements in the SOVD diagnostic context ([SWS_DM_02221]). Applications use it to traverse data structures of type DiagnosticSovdContentElementData step by step via comparison, dereferencing, and increment operators ([SWS_DM_02222]). Because all operations are specified as noexcept, checking the iteration bounds is the caller's responsibility in order to avoid undefined behavior at invalid positions.

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Context

The class ara::diag::DiagnosticSovdArrayContentElementDataConstIterator is part of the diagnostics module (diag) of the AUTOSAR Adaptive Platform ([SWS_DM_02221], AUTOSAR_AP_SWS_Diagnostics §8.60.2 “Class: DiagnosticSovdArrayContentElementDataConstIterator”). It fulfills the standard requirements for Service-Oriented Vehicle Diagnostics (SOVD) and provides a constant forward iterator for sequential data arrays. Its primary responsibility is encapsulating read-only access to individual elements of type DiagnosticSovdContentElementData ([SWS_DM_02222], [SWS_DM_02223]). The interaction partners are diagnostic applications that evaluate SOVD-compliant array contents via header file ara/diag/diagnostic_sovd_content_element_data.h without being able to modify the underlying memory structures.

Lifecycle

The class specification [SWS_DM_02221] does not list any public constructors. Instantiation of the iterator is therefore typically not expected to be performed by the application software itself, but rather provided by container methods of the higher-level data object. Question Q-a2a94d90c92beb71 (open) After creation, the iterator represents a fixed position within the array sequence.

Advancement to the respective next position is performed via the prefix increment operator operator++, which returns a reference to the incremented iterator object itself ([SWS_DM_02226]). Regarding concurrency, all member functions of the class are explicitly specified as thread-safe (thread-safe) ([SWS_DM_02222] to [SWS_DM_02226]). Multiple threads can thus concurrently read out the same or different positions. If an iterator instance is advanced in a mutating manner via operator++, this requires external synchronization in case of shared use. The lifetime of the referenced payload is likely strictly tied to the lifetime of the providing data container. Question Q-743ef89528de7a75 (open)

Usage Path

The typical usage path corresponds to the classic C++ idiom for constant iterators over a collection. At the beginning of a traversal, the caller checks the validity of the current position using the inequality operator operator!= ([SWS_DM_02225]) or the equality operator operator== ([SWS_DM_02224]) compared to the end iterator. If the iterator is within the valid range, the application accesses the element in a read-only manner:

• A constant reference DiagnosticSovdContentElementData const& is returned via the dereference operator operator* ([SWS_DM_02222]).
• A constant pointer DiagnosticSovdContentElementData const* is provided via the arrow operator operator-> ([SWS_DM_02223]), which allows direct access to member methods.

Subsequently, the caller advances the iterator by one position using operator++ ([SWS_DM_02226]) and repeats the position check until the end state is reached.

Sequence diagram: Typical sequence of stepwise iteration over SOVD array elements. Sources: [SWS_DM_02222], [SWS_DM_02225], [SWS_DM_02226]

Error Scenarios

The interface does not define special error codes or status returns in the form of ara::core::Result. All operations are specified as exception-safe (exception safe) and marked with the specifier noexcept ([SWS_DM_02222] to [SWS_DM_02226]). No C++ exceptions are thrown during runtime.

As an essential precondition for calls to operator* and operator->, the iterator must be dereferenceable. Due to the lack of error-handling mechanisms, dereferencing an invalid iterator or the end iterator is likely to lead to undefined behavior. Question Q-9144a319e654f27a (open) Likewise, it is the caller's responsibility to ensure that two compared iterators originate from the same sequence.