In this post, we will learn how to create rest service using spring boot

What is Rest Service

REST is Web services which is lightweight, maintainable, and scalable in nature.
The underlying protocol for REST is HTTP, which is the basic web protocol. REST stands for REpresentational State Transfer

What You Will learn

End of this tutorial, you will learn to create a spring boot application with Rest service

Rest Service Annotation

// This annotation used to mention a class as Controller class
@RestController

// Here we are using this to retrieve value
@GetMapping

application.properties

server.port=8080

Dependency

<parent>                                                                    
  <groupId>org.springframework.boot</groupId>                               
  <artifactId>spring-boot-starter-parent</artifactId>                       
  <version>2.2.6.RELEASE</version>                                          
  <relativePath /> <!-- lookup parent from repository -->                   
</parent>

<dependency>                                                                
  <groupId>org.springframework.boot</groupId>                               
  <artifactId>spring-boot-starter-web</artifactId>                          
</dependency>

<dependencyManagement>                                                      
  <dependencies>                                                            
    <dependency>                                                            
      <groupId>org.springframework.cloud</groupId>                          
      <artifactId>spring-cloud-dependencies</artifactId>                    
      <version>${spring-cloud.version}</version>                            
      <type>pom</type>                                                      
      <scope>import</scope>                                                 
    </dependency>                                                           
  </dependencies>                                                           
</dependencyManagement>

Sample Code

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

// This annotation used to mention a class as Controller class
@RestController
public class StudentController {

	// To Retrieve we can use Get method
	@GetMapping
	public String getName() {
		return "BeginnersBug";
	}
}

In above example we are using a simple method to retrieve a hard coded value from spring boot rest service

@RestController

This annotation is the combination of @Controller and @ResponseBody. Which will mention particular class as a Controller class

@GetMapping

This annotation for mapping HTTP GET requests onto specific handler methods.

@PostMapping

This annotation for mapping HTTP POST requests onto specific handler methods.
Note : Here we didn’t used this annotation

Time needed: 45 minutes

Steps

Create Spring boot Project
Follow this tutorial to create spring boot application
https://beginnersbug.com/how-to-create-spring-boot-application/
Create Controller Class
Once you create and import the Spring boot application in eclipse
Create a Class, Here I created as StudentController.java
Add @RestController annotation
Add @RestController annotation to the class level as like in the above sample code
Create a method to return String
Here I created a simple method with return type as String
public String getName() {return “BeginnersBug”;}
Add @GetMapping annotation
Add @GetMapping(“/name”) annotation to the method level as like in the above sample code
Edit application.properties
Navigate to application.properties under src/main/resources/
add this server.port=8080
Run
Navigate to main class. Right Click and click on RunAs –>JavaApplication
Testing
Open Browser http://localhost:8080/name . You can see the BeginnersBug in the browser

Github

https://github.com/rkumar9090/student

how to create spring boot application