# Quarkus - Hello world example using Kotlin!

Quarkus with kotlin getting started example. If you are new to the quarkus then please watch the below video to get started with Quarkus.

[%https://youtu.be/B4h9dY3H678]


# Tech Stack:
1. Kotlin
2. VSCode
3. Quarkus
4. GRadle
5. REST API


# Create Project:
Create a project using the launch Quarkus Initializr using [https://code.quarkus.io/](https://code.quarkus.io/) or you can use the VSCode editor.

![image.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1655784953030/DM_ORt6Md.png align="left")

Check the above screenshot, we have specified the following details:
1. Build Tool: Gradle with Kotlin
2. Group: org.techwasti.demo
3. Artifact: kotlin-quarkus-hello
4. Search & Pick extensions: RESTEasy JSON-B

Generate a Quarkus project and downloads it. then, Unzip the downloaded zip file and import it into your favorite IDE.


![image.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1655785235387/nZwrOD9A6.png align="left")

See the Project Structure,

![image.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1655785396989/-UMqbCWSN.png align="left")

# Quarkus core Technologies :

1. Quarkus uses RESTEasy for the JAX-RS endpoint. 
2. Quarkus uses Vert.x and Netty at its core, providing a reactive and non-blocking HTTP layer. 
3. Quarkus uses JBoss Log Manager as the default logging framework. 
4. Quartus utilizes a modified version of Undertow  that runs on top of Vert.x 
5. Quarkus uses SmallRye Config, implementation of Eclipse MicroProfile Config, for configuration data.


# For testing:
1. Quarkus uses JUnit 5 for testing. 
2. Quarkus uses rest-assured to test HTTP endpoints.


# build.gradle file

```
plugins {
    id 'java'
    id 'io.quarkus'
}

repositories {
    mavenCentral()
    mavenLocal()
}

dependencies {
    implementation enforcedPlatform("${quarkusPlatformGroupId}:${quarkusPlatformArtifactId}:${quarkusPlatformVersion}")
    implementation 'io.quarkus:quarkus-resteasy-reactive-jsonb'
    implementation 'io.quarkus:quarkus-arc'
    implementation 'io.quarkus:quarkus-resteasy-reactive'
    testImplementation 'io.quarkus:quarkus-junit5'
    testImplementation 'io.rest-assured:rest-assured'
}

group 'org.techwasti.demo'
version '1.0.0-SNAPSHOT'

java {
    sourceCompatibility = JavaVersion.VERSION_11
    targetCompatibility = JavaVersion.VERSION_11
}

compileJava {
    options.encoding = 'UTF-8'
    options.compilerArgs << '-parameters'
}

compileTestJava {
    options.encoding = 'UTF-8'
}
```

Let us see the hello world controller coding.

```
package org.techwasti.demo;

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;

@Path("/hello")
public class GreetingResource {

    @GET
    @Produces(MediaType.TEXT_PLAIN)
    public String hello() {
        return "Hello from RESTEasy Reactive";
    }
}
```

In this code snippet, we have a GET endpoint that is returning the string.
Let us run the command to build the project
```
gradle build
```
To run the application then use the below command.

```
./gradlew --console=plain quarkusDev
```
And hit URL
```
$ curl -w "\n" http://localhost:8080/hello
```

# SourceCode:

Find the complete source code here.

[https://github.com/knowledgefactory4u/Quarkus/tree/main/kotlin-quarku-helloworld](Link)

# Conclusion:
This article demonstrates you quarkus kotlin helloworld application.

**More such articles:**

[https://medium.com/techwasti](Link)

[https://www.youtube.com/channel/UCiTaHm1AYqMS4F4L9zyO7qA](Link)

[https://www.techwasti.com/](Link)

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