What is Vertx? - TutorialFlow

Introduction to Vert.x

Vert.x is a polyglot event-driven application framework that runs on the Java Virtual Machine (JVM). It is designed for building scalable, responsive, and high-performance applications. Vert.x takes the best ideas from Event-Driven Architecture (EDA), Asynchronous Programming, and Reactive Programming, making it an excellent choice for microservices, web applications, and real-time systems.

Key Features of Vert.x

Polyglot: Supports multiple programming languages including Java, JavaScript, Groovy, Ruby, and Kotlin.
Event-Driven: Uses a non-blocking, event-driven architecture for high scalability.
Asynchronous: Built-in support for asynchronous programming, enabling better resource utilization.
Modular: Provides a modular architecture that allows you to pick and choose the components you need.
Reactive: Supports the reactive programming model for building responsive and resilient applications.
High Performance: Designed for high performance and low latency.

Setting Up Vert.x

Before diving into the example, make sure you have the following prerequisites:

Java Development Kit (JDK) 8 or higher
Maven (for building the project)
An IDE like IntelliJ IDEA or Eclipse (optional but recommended)

Simple Example: Hello World with Vert.x

Let’s create a simple “Hello World” application using Vert.x. This example will demonstrate how to set up a basic HTTP server that responds with “Hello, Vert.x!” when accessed.

Step 1: Create a Maven Project

Create a new Maven project and add the following dependencies to your pom.xml file:

<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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelversion>4.0.0</modelversion>
    <groupid>com.example</groupid>
    <artifactid>vertx-hello-world</artifactid>
    <version>1.0-SNAPSHOT</version>
    <dependencies>
        <dependency>
            <groupid>io.vertx</groupid>
            <artifactid>vertx-core</artifactid>
            <version>4.3.3</version>
        </dependency>
        <dependency>
            <groupid>io.vertx</groupid>
            <artifactid>vertx-web</artifactid>
            <version>4.3.3</version>
        </dependency>
    </dependencies>
</project>

<groupid>com.example</groupid>

<artifactid>vertx-hello-world</artifactid>

<version>1.0-SNAPSHOT</version>

<groupid>io.vertx</groupid>

<artifactid>vertx-core</artifactid>

</dependency>

<groupid>io.vertx</groupid>

<artifactid>vertx-web</artifactid>

</dependency>

</dependencies>

</project>

Step 2: Create the Main Verticle

In Vert.x, a “Verticle” is a component that encapsulates a unit of deployment. Create a Java class HelloWorldVerticle:

package com.example;

import io.vertx.core.AbstractVerticle;
import io.vertx.core.Vertx;
import io.vertx.ext.web.Router;

public class HelloWorldVerticle extends AbstractVerticle {

    @Override
    public void start() {
        // Create a router object.
        Router router = Router.router(vertx);

        // Handle the "/" route
        router.route("/").handler(ctx -&gt; {
            ctx.response().putHeader("content-type", "text/plain").end("Hello, Vert.x!");
        });

        // Create the HTTP server and pass the "accept" method to the request handler.
        vertx.createHttpServer().requestHandler(router).listen(8888, http -&gt; {
            if (http.succeeded()) {
                System.out.println("HTTP server started on port 8888");
            } else {
                System.out.println("HTTP server failed to start");
            }
        });
    }

    public static void main(String[] args) {
        // Create a Vert.x instance and deploy the verticle.
        Vertx vertx = Vertx.vertx();
        vertx.deployVerticle(new HelloWorldVerticle());
    }
}

package com.example;

import io.vertx.core.AbstractVerticle;

import io.vertx.core.Vertx;

import io.vertx.ext.web.Router;

public class HelloWorldVerticle extends AbstractVerticle {

@Override

public void start() {

// Create a router object.

Router router = Router.router(vertx);

// Handle the "/" route

router.route("/").handler(ctx -> {

ctx.response().putHeader("content-type", "text/plain").end("Hello, Vert.x!");

});

// Create the HTTP server and pass the "accept" method to the request handler.

vertx.createHttpServer().requestHandler(router).listen(8888, http -> {

if (http.succeeded()) {

System.out.println("HTTP server started on port 8888");

} else {

System.out.println("HTTP server failed to start");

}

});

}

public static void main(String[] args) {

// Create a Vert.x instance and deploy the verticle.

Vertx vertx = Vertx.vertx();

vertx.deployVerticle(new HelloWorldVerticle());

}

Step 3: Run the Application

Compile and run the application using your IDE or the command line. If using the command line, navigate to the project directory and run:

mvn clean package
java -jar target/vertx-hello-world-1.0-SNAPSHOT.jar

1 2	mvn clean package java -jar target/vertx-hello-world-1.0-SNAPSHOT.jar

Step 4: Test the Application

Open your browser and navigate to http://localhost:8888. You should see the message “Hello, Vert.x!”.

Conclusion

This simple example demonstrates the basics of creating an HTTP server using Vert.x. Vert.x offers a lot more features and flexibility, allowing you to build robust and scalable applications. Explore the official Vert.x documentation to learn more about its capabilities and advanced features.