[nradov]

I don't believe that Google was really trying to achieve interoperability. If it was then they would have passed the Java Technology Compatibility Kit (TCK) tests. Other companies did that and are legally in the clear for their Java implementations. Why didn't Google?

[ghaff]

Because they were too arrogant to do so? Note that Microsoft was eventually forced to make peace with Sun over Java after a long lawsuit.

[nradov]

I'm not privy to Google's management thinking but I suspect they made that decision to save time and hit a market window. Android originally used the open source Apache Harmony Java implementation which didn't comply with the Sun (Oracle) Java license for the TCK. If Google had dropped Harmony they would have had to either write their own Java implementation from scratch or license one from another vendor like IBM. They had plenty of resources to pursue those other options but either one would have take more time and allowed Apple to build a lead in the smartphone market. So Google stuck with Harmony and now they're facing the legal consequences.