In this tutorials explain the following annotations
RestController : is used for creating a restful API services.
RequestMapping: is used for specify following request GET, PUT, POST, DELETE, etc.
Cross-origin : is an important annotation which used to calling restful API request from the front-end application
like Anqular or React or vue js or other.
Create the new Controller as
TestController
package com.springschool.firstapp.controller; import org.springframework.web.bind.annotation.CrossOrigin; import org.springframework.web.bind.annotation.PostMapping; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; @RestController @CrossOrigin @RequestMapping("api/v1/test") public class TestController { @PostMapping public void getMyApp() { String myApp = "This my First Application"; System.out.println(myApp); } }