History very approximately:

> In November 2006, Sun open-sources Java.

>In November 2007, Sun approves Google's use of Java in Android.

> April of 2009, Oracle Corp. announced that it would be acquiring Sun

Subsequently Oracle figured it could get some money from Google by requiring a license fee

http://www.zdnet.com/article/the-real-history-of-java-and-an...

It gets more complicted though, see http://www.zdnet.com/article/the-real-history-of-java-and-an... and a bunch of other stuff

Android started back when Sun was still independent and they failed to formalize the IP relationship with Sun. Google could have nabbed Sun if they wanted, but it was of no value to them when Oracle swooped in.

Google wanted to use a programming language with a lot of developers and decided to use Java

They didn't want to pay Sun for the royalties they were asking for.