type the following in the root directory of the application and Sptring Boot will startup. After that you can interact with the API in another terminal.
$ mvn spring-boot:run
$ curl -H "Content-Type: application/json" -X POST -d '{
"firstName": "Kristoffer",
"lastName": "Solberg"
}' http://localhost:8080/customers
$ curl http://localhost:8080/customers
$ curl -H "Content-Type: application/json" -X PUT -d '{
"id": 1,
"firstName": "Kristoffer",
"lastName": "Rakstad"
}' http://localhost:8080/customers/1
$ curl -X DELETE http://localhost:8080/customers/1