[kdroidFilter]

Summary

What Zayit's search needs to use NJA for Lucene on every platform (kdroidFilter/SeforimLibrary#134, kdroidFilter/Zayit#698), as general NJA features.

• jvm() targets (a desktop app): nja-client gets a JVM target whose transport calls the server's dispatcher on the calling thread. Callbacks are served back on that thread, as on iOS but without JNI. The plugin puts the façades on the target's runtime class path. The app's code is therefore the same on every platform, and the messages are still encoded.
  • Both the façades and their proxies are on that class path, so the proxies need a package of their own (njaFacade.clientPackage).
  • The generation writes nja-packages.properties, and a checkNja<Target>ClientPackages task fails clearly before the JVM target compiles if the packages collide.
• Primitive arrays: IntArray, LongArray, FloatArray and DoubleArray cross as a count and their elements.
• Sealed value hierarchies: a sealed interface or class whose nested cases are all data classes or objects travels by value (the case's index, then its fields), copied verbatim like a data class.
  • Value types now reference each other by name, so they can be recursive (a sealed value holding a list of itself, through a data class).
• Default arguments: a method's or companion's trailing default parameters get overloads, as constructors already did; the JVM applies the façade's defaults.
• AutoCloseable façades: their close() is generated as the proxy's override fun close(). It closes the JVM object, then releases it, once. It used to be generated as a member hiding JvmObject.close(), which didn't compile.
• Only the public API is exported:
  • Private and internal declarations stay out of the symbol table, and private constructor properties out of the API.
  • A class whose constructor is private, internal, or takes a type that can't cross isn't constructible from the app.
  • A function with a parameter or result that can't cross is left out. Before, the parameter was silently dropped and the result taken as Unit.
• examples/calculator:
  • It gets a jvm() target running the same suites.
  • Its proxies move into their own packages, and so do the tests.
  • New tests cover arrays, sealed values, AutoCloseable, internal constructors and default arguments.

Verification

examples/calculator: 2,008 tests pass on all three platforms: jvmTest, iosSimulatorArm64Test (jdk-mobile-27b35.3) and connectedAndroidDeviceTest (Android 11 emulator).

Notes

• Example packages: the calculator and torture façades now set clientPackage, so the example's tests are in com.example.calculator.client. Other consumers keep the default package unless they add a JVM target.
• Downstream modules: a KMP module using a module that applies NJA (Zayit's searchkit uses SeforimLibrary's search) gets Android for free through the library's AAR. Its iOS binaries, though, still have to link the runtime and copy NJA's bundle by hand. Supporting that case in the plugin would be a natural follow-up.