Step By Step Implementation
Step 1: Set up a new Spring MVC project
Create a new Maven project in your preferred IDE (e.g., IntelliJ or Eclipse or Spring Tool Suite) and add the following dependencies.
- Spring Webflux
- Mongo Db – for Database
- Lombok
XML
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>3.2.2</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.example</groupId> <artifactId>REST_Spring_Flux</artifactId> <version>0.0.1-SNAPSHOT</version> <name>REST_Spring_Flux</name> <description>Demo project for Spring Boot</description> <properties> <java.version>17</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-mongodb-reactive</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-webflux</artifactId> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <optional>true</optional> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>io.projectreactor</groupId> <artifactId>reactor-test</artifactId> <scope>test</scope> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <configuration> <excludes> <exclude> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> </exclude> </excludes> </configuration> </plugin> </plugins> </build> </project> |
Project Structure:
Step 2: Configure Mongo Db Database
# MongoDB properties
spring.data.mongodb.host=localhost
spring.data.mongodb.port=27017
spring.data.mongodb.database=student_management
- host: host property pecifies the hostname or IP address of the MongoDB server. In this example we are using localhost.
- port: property defines the port number on which the MongoDB server is running. In this example we are running our server on port no : 27010 [8080].
- database: sets the name of the MongoDB database that our Spring Boot application will connect to. In this example, the database name is “student_management”.
Step 3: Create Model Class
Student.class File:
Java
package com.example.demo.entities; import org.springframework.data.annotation.Id; import org.springframework.data.mongodb.core.mapping.Document; @Documentpublic class Student { @Id private String id; private String name; private int age; public Student(String id, String name, int age) { super(); this.id = id; this.name = name; this.age = age; } public Student() { super(); // TODO Auto-generated constructor stub } public String getId() { return id; } public void setId(String id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } } |
Note: @Document annotation indicate that this class should be mapped to a MongoDB document.
Step 4: Create Repository Interface
StudentRepository.class File:
Java
package com.example.demo.repositories; import com.example.demo.entities.*; import org.springframework.data.mongodb.repository.ReactiveMongoRepository; public interface StudentRepository extends ReactiveMongoRepository<Student, String> { } |
Step 5: Create Controller
StudentController.class File:
Java
package com.example.demo.controller; import com.example.demo.entities.Student; import com.example.demo.services.StudentService; import org.springframework.web.bind.annotation.DeleteMapping; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.PathVariable; import org.springframework.web.bind.annotation.PostMapping; import org.springframework.web.bind.annotation.RequestBody; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import reactor.core.publisher.Flux; import reactor.core.publisher.Mono; @RestController@RequestMapping("/api/students") public class StudentController { private final StudentService studentService; public StudentController(StudentService studentService) { this.studentService = studentService; } public Mono<Student> saveStudent(@RequestBody Student student) { return studentService.saveStudent(student); } @GetMapping public Flux<Student> getAllStudents() { return studentService.getAllStudents(); } @GetMapping("/{id}") public Mono<Student> getStudentById(@PathVariable String id) { return studentService.getStudentById(id); } @PostMapping public Mono<Student> createStudent(@RequestBody Student student) { return studentService.saveStudent(student); } @DeleteMapping("/{id}") public Mono<Void> deleteStudent(@PathVariable String id) { return studentService.deleteStudent(id); } } |
Step 6: Create Service Interface
StudentService.class File:
Java
package com.example.demo.services; import com.example.demo.entities.*; import reactor.core.publisher.Flux; import reactor.core.publisher.Mono; public interface StudentService { Mono<Student> saveStudent(Student student); Flux<Student> getAllStudents(); Mono<Student> getStudentById(String id); Mono<Void> deleteStudent(String id); } |
Step 7: Create ServiceImpl
StudentServiceImpl.class File:
Java
package com.example.demo.services; import com.example.demo.entities.*; import com.example.demo.repositories.StudentRepository; import org.springframework.stereotype.Service; import reactor.core.publisher.Flux; import reactor.core.publisher.Mono; @Servicepublic class StudentServiceImpl implements StudentService { private final StudentRepository studentRepository; public StudentServiceImpl( StudentRepository studentRepository) { this.studentRepository = studentRepository; } @Override public Mono<Student> saveStudent(Student student) { return studentRepository.save(student); } @Override public Flux<Student> getAllStudents() { return studentRepository.findAll(); } @Override public Mono<Student> getStudentById(String id) { return studentRepository.findById(id); } @Override public Mono<Void> deleteStudent(String id) { return studentRepository.deleteById(id); } } |
Step 8: Run the Application
Now, You can run the Spring Boot application from IDE or by using the command-line tool provided by Spring Boot.
mvn spring-boot:run
Step 9: Test the Endpoints Using Postman
POST: http://localhost:8080/api/students-- Post the student data
GET: http://localhost:8080/api/students-- Get all student details
GET: http://localhost:8080/api/students/{id} -- Get the student details by Id
Output:
Spring Boot – Reactive Programming Using Spring Webflux Framework
In this article, we will explore React programming in Spring Boot, Reactive programming is an asynchronous, non-blocking programming paradigm for developing highly responsive applications that react to external stimuli.