Swift, likewise, is Apple's baby, although it's been made into an open source project -- which is expected to lead to major cross-platform adoption in the long run. Google adopting Swift as a long-term pivot makes sense if the plan is to reduce dependency on a platform and a runtime that's fraught with proprietary concerns.
But again, there's little question Swift's direction is influenced chiefly by Apple. It isn't likely Google wants to make itself dependent, even if only indirectly, on a key competitor -- not even if the technology in question is open source. In theory, Google could fork Swift and take control of the fork, but it would be stuck with the maintenance and management overhead of an entire language.
Switching to Go would be more in line with Google's thinking
If Google really wants to disassociate itself with third-party languages and runtimes, it wouldn't ditch Java for Swift. It would make more sense to turn to the language, runtime, and toolchain built in-house: Go, also know as Golang.
Go can already be used for mobile development. Versions 1.5 and up of Golang provided support for both Android and iOS, and with the "app" package, devs can write all-Go apps for both platforms. That said, mobile support for Go is stillclassified as experimental.
If Google intended to make Go or Swift into a complement to Java on Android -- let alone replace it -- a lot more work would be in order. It's a safe bet that Android will remain ensconced on Java for a long time to come.
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