# Different codeunit types

Most likely you will need to create a [Formevents](https://docs.tsnocode.com/books/codeunit-reference/chapter/formevents) that will allow specific changes for a solution, during views, updates or exports.

Most interactions wil require interaction with the following objects

- [Security](https://docs.tsnocode.com/books/java-api/page/security)
- [Command](https://docs.tsnocode.com/books/java-api/page/command)
- [Session](https://docs.tsnocode.com/books/java-api/page/sessions)
- [Context](https://docs.tsnocode.com/books/java-api/page/context)
- [DbConnection](https://docs.tsnocode.com/books/java-api/page/dbconnection)
- [EventHandler](https://docs.tsnocode.com/books/java-api/page/eventhandler)