You can download the latest Java broker package from the Download Page.
It is recommended that you confirm the integrity of the download by verifying the PGP signature matches that available on the site. Instrutions are given on the download page.
The broker has an optional message store implementations backed by Oracle BDB JE. If you wish to use these stores you will need to provide the optional Oracle BDB JE dependency. For more details, see Section 10.4, “BDB Message Store”