refine getPluginsAsMap

[XenoAmess]

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[elharo]

I don't really follow the purpose of this PR. maybe someone else will.

[elharo]

why do we need this? Why not just call flushPluginMap? It's only a one-liner

[XenoAmess]

because it is weird to register flushPluginMap as a function in the base class.
the idea was, cleanDelegateCache be a abstract class, and the flushPluginMap is only what this specific situation in this class needs.
well, we decide to continue using modello, didn't we.....

[elharo]

Then maybe inline flushPluginMap into this method?

[gnodet]

I'd rather avoid any breakage in the 3.x model since it's supposed to be stable.

[elharo]

I don't see a specific problem but the thread safety here makes me nervous.

[XenoAmess]

I don't really follow the purpose of this PR. maybe someone else will.

@elharo
for not constructing the map in getPluginsAsMap every time.
getting a plugin from a map is just a O(1) (if we use hashmap based maps here)
but the current impl nees a O(n) full map building.
and the most cases when we invoke this function, we just want to use it with : 'getPluginsAsMap().get(key)', which is costing when the pluginMap is really big.

Though the bitter truth is adding the prs I opened last weekend in maven project up, has about 3% performance increasing on that test on my machine, but the maven-resolver pr I opened has 30%+ performance refnie.
bottleneck is not on maven, but resolver...

[elharo]

Instead of building a map, lazily or not, could we instead only have a map and iterate through that instead of a list of plugins?

[elharo]

Then maybe inline flushPluginMap into this method?

[XenoAmess]

Instead of building a map, lazily or not, could we instead only have a map and iterate through that instead of a list of plugins?

Yes that is thr original thought. Though I have no idea how to make modello generate it to a map, not a list
A LinkedHashMap can solve anything in this case. though modello...well, I have even no idea now to make a new grammar to tell the generator to generate this field as a LinkedHashMap, using which param as key...
I don't really familiar with modello...though maybe I can have a try when have time.

[elharo]

a map of plugin keys to plugins

[elharo]

Modello isn't very well documented or supported. If you make the plugins field a map instead of a list, it might work, but it might not. I'm not sure. There might be some way to add custom code and replace default generated code with custom code, but again I don't really know.

[elharo]

needs Override annotation