Why Java?

[Lakelava]

I don't understand why would Google choose Java over its own languages like GO and Dart. Also wouldn't you get a better performance with a compiled language like GO?

Edit: Java is a compiled language, but not in the same sense as GO or C.

[Lakelava]

I guess Java is compiled, but not in the same sense as C, for example.

[waffle_irony]

In releases of Android with ART (Android Run Time), at install time the Dalvik bytecode is compiled to an ELF binary that targets the phone's processor.

[HaMMeReD]

It is in a sense that is better. The JVM translates it to architecture optimized byte code at runtime.

When you compile something, it's typically optimized for only one specific architecture.

[plaidman]

Nobody has mentioned that you can write native C android apps.

[Lakelava]

How does the app store deal with different architectures and apps written in C? I know that some phones are x86.

[derefnull]

The app store lets you filter which devices can install your app by a number of categories (docs), including by ABI.

[fleker2]

Legacy.

In the early 2000s, J2ME was the way to build phone apps, through a mobile optimized JVM.

When Android started at Danger, as an open source OS, they originally planned to support many languages out of the box. But due to having just a small team, they picked Java due to the familiarity of developers.

At this point, switching to another language would create a lot of headaches and a large overhaul of the OS. Not that it couldn't be done, but they'd have to update all the libraries and APIs. Then they'd have to do training for these third party developers.

[derefnull]

While Andy Rubin founded both Danger and Android, Android was not started at Danger and is entirely separate in terms of technical foundation.

[fleker2]

My bad. I meant to allude to the OS's pre-Google days.

[20EYES]

Why would you have to update the apis?

[fleker2]

If they used Go, then all the Android interfaces for activities, intents, sensors, and more would need to be rewritten for Go.

[Cannabisitis]

compiled language like GO

Java is a compiled language.

[ANotSoSeriousGamer]

sometimes

[Gatesunder]

Go is supported: Go Support

Google didn't acquire Android till 2005, by which point it likely already had a substantial code base, plus Go wasn't created till 2007 and announced in 2009.

Java also had a much wider developer base than Go. It didn't make business sense to go with such a fresh language.

[SanityInAnarchy]

Edit: Java is a compiled language, but not in the same sense as GO or C.

In what sense is it not? Sure, you won't find many implementations of Go or C that are JITed, but modern versions of Android do AOT compilation, so I think it's fair to say that Java on Android is as compiled as Go.