[koko775]

This is a fair point but an API is -always- going to be running in an ecosystem. If it's the Java ecosystem, not using a namespace flies in the face of tens or hundreds of thousands of people's conception of common convention. Which is most definitely not wise, even if src/main/java/reverse/dns/namespace is aesthetically unpleasing to some.

Things like the Play! Framework can get away with it because the framework is basically an exoskeleton around the Java code rather than a traditional container.