Spring Scala With Spring Boot | Spring Scala

Introduction

Spring Boot is a powerful framework for building Java applications, but did you know you can also use it with Scala? In this tutorial, we'll explore how to set up a Spring Boot application using Scala, covering all the essentials from project setup to creating RESTful services.

Setting Up Your Environment

Before we start coding, ensure you have the following installed on your machine:

Java Development Kit (JDK) 8 or higher
Scala Build Tool (SBT)
Spring Boot
IDE (IntelliJ IDEA is recommended for Scala development)

You can verify your installations by running the following commands:

java -version

scala -version

sbt sbtVersion

Creating a New Spring Boot Project

Start by creating a new directory for your project and navigate into it. Then, create a new SBT project structure:

mkdir spring-scala-app

cd spring-scala-app

sbt new scala/scala-seed.g8

This command generates a basic Scala project. You can then modify the generated files to integrate Spring Boot.

Adding Dependencies

Open the `build.sbt` file and add the necessary dependencies for Spring Boot:

name := "spring-scala-app"

version := "0.1"

scalaVersion := "2.13.6"

libraryDependencies ++= Seq(
  "org.springframework.boot" % "spring-boot-starter" % "2.5.4",
  "org.springframework.boot" % "spring-boot-starter-web" % "2.5.4",
  "org.springframework.boot" % "spring-boot-starter-test" % "2.5.4" % "test"
)

This configuration sets up the Spring Boot starter, web, and test dependencies for your Scala application.

Creating a Simple REST Controller

Next, we will create a simple REST controller. Create a package for your application and add a new Scala file called `HelloController.scala`.

mkdir -p src/main/scala/com/example/controller

touch src/main/scala/com/example/controller/HelloController.scala

Open `HelloController.scala` and add the following code:

package com.example.controller

import org.springframework.web.bind.annotation.{GetMapping, RestController}

@RestController
class HelloController {

  @GetMapping(Array("/hello"))
  def hello(): String = {
    "Hello, Spring Scala with Spring Boot!"
  }
}

Running Your Application

To run your application, create a new Scala file called `Application.scala` in the same package:

touch src/main/scala/com/example/Application.scala

Add the following code to `Application.scala`:

package com.example

import org.springframework.boot.SpringApplication
import org.springframework.boot.autoconfigure.SpringBootApplication

@SpringBootApplication
object Application {
  def main(args: Array[String]): Unit = {
    SpringApplication.run(classOf[Application], args: _*)
  }
}

Now, return to your terminal and run the application using SBT:

sbt run

Once the application is running, you can access the endpoint at http://localhost:8080/hello.

Testing Your Application

To test the application, you can use a tool like Postman or curl. Here's how to test using curl:

curl http://localhost:8080/hello

You should see the response: "Hello, Spring Scala with Spring Boot!".

Conclusion

In this tutorial, you learned how to set up a Spring Boot application using Scala. You created a simple REST controller and ran your application. This is just the beginning, as you can explore various Spring Boot features like data access, security, and more with Scala.

Spring Scala with Spring Boot Tutorial