Apple made Swift open source last year and apparently Google, Facebook and Uber are interested in making it a “first class” language for Android.
Although the idea is that Swift will not replace Java, at least at first, it seems that Google has had a gutsful of Oracle’s attempts to screw money out of the search engine outfit.
Swift was created as a replacement for Objective C, and is pretty easy to code. It was introduced at WWDC 2014, and has major support from IBM as well as a variety of major apps like Lyft, Pixelmator and Vimeo that have all rebuilt iOS apps with Swift.
However it would be a bit of a mess at first. Google would also have to make its entire standard library Swift-ready, and support the language in APIs and SDKs. Some low-level Android APIs are C++, which Swift cannot bridge to. Higher level Java APIs would have to be re-written.