eclipse-aascw / aas-core-codegen / 35240523421

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Compose the Java JSON de-serialization (#704)

Three quarters of the generated ``Jsonization.java`` was
de-serialization, and two thirds of that was one shape repeated. Every
``case`` of a property loop inlined its own procedure: a check for a
JSON null, a cast to an array for a list or a tuple carrying an error of
its own, the call, a check of the error, a ``prependSegment`` naming
that property and a ``castTo`` of the failure.

Nothing names the property any more, because the loop already has it.
The key *is* the JSON name, so ``prependName(parsed, key)`` replaces the
436 lines which spelled it out, and a ``case`` now carries nothing but
the call and the assignment:

    case "semanticId": {
      final Reporting.Result<? extends IReference> parsed =
        tryReferenceFrom(value);
      if (parsed.isError()) {
        return prependName(parsed, key);
      }
      theSemanticId = parsed.getResult();
      break;
    }

``parseArray`` and ``parseTuple{N}`` take the JSON node rather than an
already-cast array, which deletes the inline casts. A list and a tuple
are the only types with no function of their own to be named after, so
they -- and only they -- are composed out of the parsers of their items
into a function named by the moniker of the type:
``parseListOf_IExtension``. Eighteen of them serve all 124 list-typed
properties of the AAS meta-model. Composing at the call site instead
would be just as fast, as a method reference to a static method captures
nothing and the JVM caches it; it would, however, leave one
``invokedynamic`` call site per property rather than one per item type.

The moniker grammar naming a composed parser is the one the XML side
already uses, moved verbatim from ``java/lib/_generate_xmlization.py``
to ``java/common.py``.

The model type is now handled exactly once on every path. It is checked
before the loop instead of in it, so a wrong one is reported without
de-serializing any of the properties first, and its ``case`` on... (continued)

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