There is an obvious explanation for the documentation to be visible: it is that its owners, Sun, might have opened their books during the Apache Harmony project.
Well, the thing with copyright is that there are rules and if you make those files available for one project, you have essentially made them available for everyone. Not that I think that the issue will be decided on this, but worth noting. Google certainly hasn't covered itself with glory either. It could probably have got official blessing from Sun for its approach at the time, but seemed determined to want to avoid this.
The potential fallout for making a public API entirely subject to copyright (you get to decide who can implement it and how) is huge and something that Oracle should itself be worried about: there are bound to be parts of its database code built in a similar way.
Biting the hand that feeds IT
