Check out example codes for "mkyong restful web services spring boot examples post". It will help you in understanding the concepts better.

Code Example 1

> curl -v -X PATCH localhost:8080/books/4 -H "Content-type:application/json" -d "{\"author\":\"oracle\"}"
*   Trying ::1...
* TCP_NODELAY set
* Connected to localhost (::1) port 8080 (#0)
> PATCH /books/4 HTTP/1.1
> Host: localhost:8080
> User-Agent: curl/7.55.1
> Accept: <strong>/</strong>
> Content-type:application/json
> Content-Length: 19
>
* upload completely sent off: 19 out of 19 bytes
< HTTP/1.1 200
< Content-Type: application/json;charset=UTF-8
< Transfer-Encoding: chunked
< Date: Tue, 19 Feb 2019 07:39:53 GMT

{
	"id":4,
	"name":"Spring Forever",
	"author":"oracle",
	"price":9.99
}

Code Example 2

> curl -v localhost:8080/books

*   Trying ::1...
* TCP_NODELAY set
* Connected to localhost (::1) port 8080 (#0)
> GET /books HTTP/1.1
> Host: localhost:8080
> User-Agent: curl/7.55.1
> Accept: <strong>/</strong>
>
< HTTP/1.1 200
< Content-Type: application/json;charset=UTF-8
< Transfer-Encoding: chunked
< Date: Tue, 19 Feb 2019 06:33:57 GMT
<

[
	{"id":1,"name":"A Guide to the Bodhisattva Way of Life","author":"Santideva","price":15.41},
	{"id":2,"name":"The Life-Changing Magic of Tidying Up","author":"Marie Kondo","price":9.69},
	{"id":3,"name":"Refactoring: Improving the Design of Existing Code","author":"Martin Fowler","price":47.99}
]

Code Example 3

$ mvn spring-boot:run

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