Can I use the RMI registry for the commercial purpose without having to pay Sun royalties or licensing fees for the same? My guess is I don't since it is a part of the JRE, but what is the definitive answer on this?

Luigi Viggiano

RMI is a part of Java Core APIs, and it is subject to the same license as JRE/JSDK. i.e. you have not to pay any royalty, it's free.

When you download the JRE or JSDK you are presented a license that is applicable to all the downloaded software, including RMI since it is a part of the JSDK/JRE archives.

All the core APIs and standard extensions (javax.* packages) are free for use within your products.