Reactive applications are becoming increasingly popular due to their ability to handle asynchronous and event-driven programming. In this blog post, we will explore how to build reactive applications using GlassFish, a widely-used application server, and Reactor, a powerful reactive programming framework for Java.

What is GlassFish?

GlassFish is an open-source, Java EE-compatible application server that provides a runtime environment for deploying and running Java applications. It supports the latest Java EE standards and offers a wide range of features and tools for building enterprise applications.

What is Reactor?

Reactor is a reactive programming framework for building scalable, resilient, and event-driven applications in Java. It provides an extensive set of operators and utilities for handling asynchronous streams of data, along with built-in support for backpressure and error handling.

Setting up GlassFish with Reactor

1. Download GlassFish: Start by downloading and installing GlassFish from the official website. Follow the installation instructions provided to set up GlassFish on your system.

2. Create a Maven project: Open your favorite IDE and create a new Maven project. Add the necessary dependencies for GlassFish and Reactor in the pom.xml file.

   <dependencies>
       <dependency>
           <groupId>org.glassfish.main.extras</groupId>
           <artifactId>glassfish-reactor</artifactId>
           <version>5.1.0</version>
       </dependency>
       <!-- Other dependencies -->
   </dependencies>
   

3. Create a Reactive Application: Write your reactive application code using Reactor’s API. Below is an example of a simple reactive application that processes streams of data.

   import reactor.core.publisher.Flux;
   
   public class ReactiveApp {
       public static void main(String[] args) {
           Flux.just("Apple", "Banana", "Orange")
               .map(String::toUpperCase)
               .subscribe(System.out::println);
       }
   }
   

4. Deploy to GlassFish: Build your Maven project using the appropriate command (mvn clean install) and generate a WAR file. Deploy the generated WAR file to GlassFish by copying it to the domains/domain1/autodeploy directory.

5. Start GlassFish: Start GlassFish by executing the appropriate command (./asadmin start-domain) in the GlassFish installation directory.

6. Access the Application: Once GlassFish is up and running, you can access your reactive application by navigating to http://localhost:8080/{your-application-name} in your web browser.

Conclusion

In this blog post, we have seen how to build reactive applications using GlassFish and Reactor framework in Java. By combining the power of GlassFish as an application server and Reactor as a reactive programming framework, you can easily build scalable and resilient applications that handle asynchronous and event-driven programming. Give it a try and harness the benefits of reactive programming in your Java applications!

#Tech #ReactiveProgramming