weblogic application server and after they acquired Sun you see that java is becoming the main application language for Oracle.
We have seen recently some legal battles between Google and Oracle about parts of Java and this is showing that Oracle is willing to go into battle mode for Java. However this is not meaning that they want to make java as proprietary as possible. One of the latest cases showing this is the release of ADF Essentials. ADF is the Oracle Application Development framework which is a proprietary development framework build by Oracle to support the development community and which is also used heavily by Oracle development teams internally for product development. One of the things about ADF is that you need theOracle weblogic server to run it (officially). This automatically rules out that ADF can be used to create open source products and it is limiting the adoption of ADF as you have a vendor lock with Oracle with the application server.
Now Oracle has launched ADF Essentials which is able to run not only on weblogic, it can also run on for example GlassFish or other application servers like for example IBM WebSphere. ADF Essentials can be used for free and you no longer have a vendor lock on the application server. ADF Essentials is a stripped down version of the commercial ADF version.
ADF Essentials is important for Oracle as they hope to boost the adoption of ADF with it, not only the Essentials version but also the commercial version. The commercial vision of Oracle behind Essentials is (most likely) that it will make that ADF will get more popular and that more developers will start developing in a ADF way and by doing so not only make the product base bigger for ADF Essentials, it should also make the adoption of the commercial version of ADF bigger and by doing so boost up the license revenue coming from the sales of WebLogic licenses.
If you are a company who will be building applications based upon Oracle ADF Essentials it is good to take some note of the ADF Essentials license policy. If we take a look at the ADF essentials license policy we note the following;
You are bound by the Oracle Technology Network ("OTN") License Agreement terms. The OTN License Agreement terms also apply to all updates you receive under your Technology Track subscription.
this means you will have to review the OTN License Agreement in debt to be sure what you can and cannot do with ADF Essentials from a legal point of view. Most important to know is the following: Oracle ADF Essentials is a free to develop and deploy packaging of the key core technologies of Oracle ADF.