Now, we know Java was invented by Sun that was later acquired by Oracle, along with all Java patents and coding. We also know that Android is loosely based on Linux, but includes various Java apps stacked on the core, and the renowned Dalvik virtual machine includes a JIT (just-in-time) Java compiler in Android 2.2, making it the fast beast it is.
Oracle put two and two together and decided there is bread (and circus) in those dusty Java patents in the basement, and did what every self-respecting US company would do – they sued. Oracle has hired David Boies, a lawyer whose career includes cases like United States vs. Microsoft (where Java was an issue as well), Bush vs. Gore and numerous other high-profile cases in and out of the tech industry.
On a separate Sun vs Microsoft case, the Redmond giant ultimately ended up paying $1bln compensation to Sun for infringing on its Java patents, so Google better watch out, there might be merit in Oracle's case.