Hi, I downloaded the source code and successfully build it, but now I don't know how to correctly install it on my computer because I have only install it using the dpk package and don't know where does the files goes.
To be able to install, you have to package it somehow. You should look into tools that let you create installers/packages. Openfire's source build doesn't provide it automatically.
Is complicated to package? I was thinking to only change the file (java, .jar, .class, etc) that I changed
Do you need to install it? target\openfire contains everything you need, just copy it to wherever you want it and run bin\openfire.bat or bin\openfire.sh