I work at Product Mgmt at HashiCorp. There is a Java Spring example here that uses buildpacks from either Heroku, Cloud Foundry Paketo (VMware Tanzu team that works closely with Spring), and GCP Buildpacks.

https://github.com/hashicorp/waypoint-examples/tree/main/doc...

You don't have to use buildpacks, you could use the Docker plugin with a Dockerfile as in this reactjs example: https://github.com/hashicorp/waypoint-examples/tree/main/doc...