- okta-java-sdk is for management of Okta entities with API (like users, groups, etc). If you are not going to do things like that and only planning to SSO with SAML, I’d say, you don’t need it
- You can use whatever SAML library you are comfortable with
- See above #2
- I think Okta has an article on SAML integration. What I was able to find is - https://developer.okta.com/docs/guides/build-sso-integration/saml2/create-your-app/ Start from here and research more