OpenJDK != Sun Java JDK, at least that was the situation last time I checked. There are still several components not released to the public, but Sun's effort is nonetheless praiseworthy. Since Sun is behind the OpenJDK project, you are technically correct - they did release the tools and the VM as open-source, just not the `original` thing - where Adobe released Flex SDK that is their main toolchain used by their own IDEs (there is no `commercial Flex SDK` and `OpenFlexSDK`).

It's a matter of semantics, I didn't mean to say that Java is closed-source or restricted in any way, far from it. I'd take it even a step further and speculate that Adobe would never open the Flash platform as they did if Sun didn't make the first move.