How to Create a Spring Boot Application using Kotlin and Gradle

A few months ago I wrote an article showing how to create a simple Spring Boot application using Java, you can see it by clicking here.

Now, I am going to show you, how to create the same application using Kotlin and Gradle.

The requirements are:

• Gradle installed;
• Text Editor installed, I recommend Visual Studio Code

Now, you must go to the following website:

• Spring Initializr

Choose to generate a Gradle Project with Kotlin and fill in the group and the artifact fields. Example:

• Group: com.mydomain
• Artifact: demo

In the Search for dependencies field fill in: Web

The options chosen will be as the image below:

Now, click on the Generate Project button

So, download the ZIP file and unzip it.

Using a text editor ( I recommend Visual Studio Code), open the demo folder.

We are going to create the web controller file named HelloWorldController.kt at demo\src\main\kotlin\com\example\demo\\ folder:

Your respective code will be:

package com.example.demo

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

@RestController
class HelloWorldController {

    @GetMapping("/")
    fun index() = "Hello, World!"

}

Now, using the command prompt you can initialize the application using the command: gradle bootrun. It is going to use Gradle. After the execution, you will see the success message referring to the initialization from an embedded Apache Tomcat.

** <==========—> 80% EXECUTING [1m 40s]

:bootRun ** **

So, access http://localhost:8080 in the web browser.

Finally, your first Spring Boot application with Kotlin and Gradle was created.

Thanks for reading.