Building a Hypermedia-Driven RESTful Web Service using Heteoas

                           Spring Boot Hateoas Example

Purpose: In this post, we will learn how we can create a Hibermedia link in API and Testing in spring boot. The steps are given below.

1. Setup and Create Project: Visit here. Spring Boot Rest API Hello World Examples.

Next Step. Spring Boot Parent Dependencies.

  <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.3.0.M1</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>

Next Step. Add Heteoas Dependencies.

<dependency>

    <groupId>org.springframework.boot</groupId>

    <artifactId>spring-boot-starter-hateoas</artifactId>

</dependency>

Next Step. Spring Boot main class.

Class: Application.java

Note: @SpringBootApplication=@Configuration+ @EnableAutoConfiguration+ @ComponentScan.

package com.bce;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;

@SpringBootApplication
public class Application {
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }

}

Next Step. Create Rest Controller.

package com.bce.controller;
import static org.springframework.hateoas.server.mvc.WebMvcLinkBuilder.linkTo;
import static org.springframework.hateoas.server.mvc.WebMvcLinkBuilder.methodOn;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.hateoas.EntityModel;
import org.springframework.hateoas.server.mvc.WebMvcLinkBuilder;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import com.bce.model.Employee;
import com.bce.service.EmployeeService;
@RestController
public class EmployeeController {
    @Autowired
    EmployeeService employeeService;
    @GetMapping("/employee")
    public List<Employee> findAll() {
        return employeeService.getAllEmployee();
    }
    @GetMapping("/employee/{id}")
    public EntityModel<Employee> findEmployeeById(@PathVariable long id) {
        EntityModel<Employee> resource = EntityModel.of(employeeService.getEmployeeById(id));
        WebMvcLinkBuilder linkTo = linkTo(methodOn(this.getClass()).findAll());
        resource.add(linkTo.withRel("all-employees"));
        return resource;
    }
}

Next Step. Server Port:  The default server port is 8080. Wish you want to change open application.properties and add the below line.

server.port=8081

Download Code from GitHub.  Download