This project sends SNMPv3 traps using the snmp4j library.
Since there aren't any well documented examples I have decided to create one out of my own experience with implementing this feature.
To test that the traps are really being received a docker-compose.yml is included in /src/test/resources/ which will setup an instance of snmptrapd running in an Ubuntu container. Running the app with mvn spring-boot:run will send a single trap which can be viewed in the container's stdout.
Navigate to /src/test/resources/ and run docker compose up. You can follow the trap receiving side here.
In the project root run mvn clean package followed by mvn spring-boot:run. This will run the application and send a trap.