結論:どちらも同じなので意味的に適切だと思う方を使ってよい 発端は以下のツイートだ。 たしかに、公式ドキュメントには以下のように書いてある。 On devices without a JIT, it is true that invoking methods via a variable with an exact type rather than an interface is slightly more efficient. (So, for example, it was cheaper to invoke methods on a HashMap map than a Map map, even though in both cases the map was a HashMap.) It was not the case that this was 2x slower; the
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