WildFly, Jakarta EE 10 & Maven: A Developer’s Guide

Let’s dive into using WildFly, Jakarta EE 10, and Maven together! This guide is designed to walk you through setting up your development environment and deploying Jakarta EE 10 applications on WildFly using Maven. It’s packed with practical examples and explanations to get you up and running quickly. So, buckle up, and let’s get started!

Setting Up Your Development Environment

First, you need to ensure you have the essential tools installed. These include the Java Development Kit (JDK), Maven, and an Integrated Development Environment (IDE). We’ll go over each of these in detail. The JDK is crucial as it provides the necessary compilers and runtime environment for Java applications. For Jakarta EE 10, you’ll need a JDK that supports at least Java 11, but using the latest LTS (Long-Term Support) version, like Java 17 or 21, is highly recommended. You can download the JDK from various vendors such as Oracle, Adoptium (Eclipse Temurin), or Azul Zulu. Once downloaded, ensure you set the JAVA_HOME environment variable to point to your JDK installation directory. This allows Maven and other tools to locate your JDK.

Next up is Maven . Maven is a powerful build automation tool that simplifies dependency management and project builds. You can download Maven from the Apache Maven website. After downloading, extract the archive to a directory of your choice. Similar to the JDK, you need to configure environment variables. Add the M2_HOME variable pointing to your Maven installation directory and update the PATH variable to include the bin directory of your Maven installation. This makes the mvn command available from your terminal. Verify the installation by running mvn -v in your terminal. You should see the Maven version and other details printed out.

Finally, choose an IDE. Popular choices include IntelliJ IDEA, Eclipse, and VS Code with Java extensions. IntelliJ IDEA offers excellent support for Jakarta EE and Maven out of the box. Eclipse requires some additional plugins, such as the Eclipse Enterprise Java Developer Tools. VS Code, being lightweight, can be enhanced with extensions like the Java Extension Pack from Microsoft. Regardless of your choice, ensure your IDE is configured to use the correct JDK and Maven installations. This usually involves pointing the IDE to the JAVA_HOME and Maven installation directories in the IDE’s settings. With these tools set up, you’re ready to start developing Jakarta EE 10 applications on WildFly.

Creating a Jakarta EE 10 Project with Maven

Creating a Jakarta EE 10 project with Maven is straightforward. Maven uses archetypes, which are project templates, to bootstrap new projects. For Jakarta EE 10, you can use the jakartaee10-webapp-archetype to create a basic web application. Open your terminal and run the following Maven command:

mvn archetype:generate \
    -DgroupId=com.example \
    -DartifactId=my-jakartaee10-app \
    -DarchetypeArtifactId=jakartaee10-webapp-archetype \
    -DarchetypeGroupId=org.codehaus.mojo.archetypes \
    -Dversion=1.0-SNAPSHOT

This command tells Maven to generate a new project with the specified groupId , artifactId , and archetype . The groupId is the package name for your project, artifactId is the name of your project, and archetypeArtifactId specifies the archetype to use. After running this command, Maven will create a new directory named my-jakartaee10-app containing the basic project structure. Navigate into this directory using cd my-jakartaee10-app . Inside, you’ll find the pom.xml file, which is the heart of your Maven project. It defines the project’s dependencies, build configurations, and plugins.

Open the pom.xml file in your IDE. You’ll see the basic structure of a Maven project. The important sections include <dependencies> , where you define the project’s dependencies on Jakarta EE APIs and other libraries, and <build> , where you configure the build process, such as specifying the Java compiler version and adding plugins. For a Jakarta EE 10 web application, you’ll typically need dependencies on jakarta.platform:jakarta.jakartaee-api:10.0.0 . This dependency provides access to all the Jakarta EE 10 APIs. Add this dependency to your pom.xml file within the <dependencies> section. You might also need to configure the maven-compiler-plugin to use Java 11 or later. This ensures that your code is compiled with the correct Java version. With the basic project structure and dependencies in place, you can start adding your application code. The src/main/java directory is where you’ll put your Java source code, and the src/main/webapp directory is for your web resources like HTML, CSS, and JavaScript files.

Configuring WildFly for Jakarta EE 10

Configuring WildFly for Jakarta EE 10 is generally straightforward, as WildFly is a fully compliant Jakarta EE application server. Download the latest version of WildFly from the official WildFly website. Ensure you download a version that supports Jakarta EE 10. After downloading, extract the archive to a directory of your choice. To start WildFly, navigate to the bin directory within your WildFly installation and run the standalone.sh (or standalone.bat on Windows) script. This starts WildFly in standalone mode, which is suitable for development and testing.

Once WildFly is running, you can access the administration console by opening your web browser and navigating to http://localhost:9990 . The default username and password are admin and a blank password. You’ll be prompted to create a new password upon your first login. The administration console allows you to manage various aspects of WildFly, such as deploying applications, configuring data sources, and managing security realms. However, for simple deployments, you typically don’t need to use the administration console directly. You can deploy your application by simply copying the WAR file to the deployments directory within the standalone directory of your WildFly installation. WildFly automatically detects the new WAR file and deploys the application.

For more advanced configurations, you can modify the standalone.xml file located in the standalone/configuration directory. This file contains the main configuration settings for WildFly. You can configure data sources, security realms, and other settings by editing this file. However, be cautious when modifying this file, as incorrect settings can prevent WildFly from starting. It’s always a good idea to back up the file before making any changes. WildFly also supports various deployment options, such as using the WildFly Maven plugin or the WildFly CLI. These options provide more control over the deployment process and are useful for automating deployments in a CI/CD environment. By configuring WildFly correctly, you can ensure that your Jakarta EE 10 applications run smoothly and efficiently.

Deploying Your Application to WildFly Using Maven

Deploying your Jakarta EE 10 application to WildFly using Maven can be achieved through the WildFly Maven plugin. This plugin simplifies the deployment process by allowing you to deploy your application directly from your Maven build. To use the WildFly Maven plugin, you need to add it to your pom.xml file within the <plugins> section of the <build> element. Add the following plugin configuration:

<plugin>
    <groupId>org.wildfly.plugins</groupId>
    <artifactId>wildfly-maven-plugin</artifactId>
    <version>3.0.1.Final</version>
    <configuration>
        <hostname>${wildfly.hostname}</hostname>
        <port>${wildfly.port}</port>
        <username>${wildfly.username}</username>
        <password>${wildfly.password}</password>
    </configuration>
</plugin>

In this configuration, you specify the groupId , artifactId , and version of the WildFly Maven plugin. The <configuration> section allows you to configure various settings, such as the hostname, port, username, and password for your WildFly server. You can define these properties in your pom.xml file or pass them as command-line arguments when running Maven. For example:

<properties>
    <wildfly.hostname>localhost</wildfly.hostname>
    <wildfly.port>9990</wildfly.port>
    <wildfly.username>admin</wildfly.username>
    <wildfly.password>YOUR_ADMIN_PASSWORD</wildfly.password>
</properties>

Replace YOUR_ADMIN_PASSWORD with the actual password for your WildFly administrator user. Once the plugin is configured, you can deploy your application by running the following Maven command:

mvn wildfly:deploy

This command tells Maven to deploy your application to the WildFly server specified in the plugin configuration. The plugin automatically builds your application, packages it as a WAR file, and deploys it to WildFly. You can also undeploy your application using the following command:

mvn wildfly:undeploy

The WildFly Maven plugin also supports other goals, such as wildfly:start and wildfly:stop , which allow you to start and stop the WildFly server from Maven. This can be useful for automating integration tests or managing your development environment. By using the WildFly Maven plugin, you can streamline the deployment process and easily deploy your Jakarta EE 10 applications to WildFly from your Maven build.

Jakarta EE 10 Features and Examples

Jakarta EE 10 introduces several new features and enhancements that make it easier to develop enterprise applications. Some of the key features include support for newer versions of specifications like CDI, Jakarta RESTful Web Services, and Jakarta Persistence. For example, let’s look at a simple example using Jakarta RESTful Web Services. Create a new Java class in the src/main/java directory, named HelloResource.java :

package com.example;

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

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

    @GET
    @Produces(MediaType.TEXT_PLAIN)
    public String hello() {
        return "Hello, Jakarta EE 10!";
    }
}

This class defines a simple REST endpoint that returns the string “Hello, Jakarta EE 10!”. The @Path annotation specifies the URL path for the endpoint, and the @GET annotation indicates that this method handles GET requests. The @Produces annotation specifies the media type of the response.

To deploy this application to WildFly, build the project using Maven:

mvn clean install

Then, deploy the application using the WildFly Maven plugin:

mvn wildfly:deploy

Once the application is deployed, you can access the endpoint by opening your web browser and navigating to http://localhost:8080/my-jakartaee10-app/hello . You should see the message “Hello, Jakarta EE 10!” displayed in your browser.

Another important feature of Jakarta EE 10 is the improved support for CDI (Contexts and Dependency Injection). CDI allows you to easily manage dependencies and inject them into your application components. For example, you can create a CDI bean that provides configuration settings:

package com.example;

import jakarta.enterprise.context.ApplicationScoped;
import jakarta.inject.Named;

@ApplicationScoped
@Named("config")
public class AppConfig {

    private String appName = "My Jakarta EE 10 App";

    public String getAppName() {
        return appName;
    }
}

This class defines a CDI bean named config that is application-scoped. You can inject this bean into other components using the @Inject annotation:

package com.example;

import jakarta.inject.Inject;
import jakarta.ws.rs.GET;
import jakarta.ws.rs.Path;
import jakarta.ws.rs.Produces;
import jakarta.ws.rs.core.MediaType;

@Path("/config")
public class ConfigResource {

    @Inject
    @Named("config")
    private AppConfig config;

    @GET
    @Produces(MediaType.TEXT_PLAIN)
    public String getConfig() {
        return "App Name: " + config.getAppName();
    }
}

In this example, the ConfigResource class injects the AppConfig bean and uses it to retrieve the application name. By leveraging these features, you can build robust and maintainable Jakarta EE 10 applications on WildFly with Maven.

Troubleshooting Common Issues

When working with WildFly, Jakarta EE 10, and Maven, you might encounter some common issues. One frequent problem is dependency conflicts. Maven’s dependency management is generally good at resolving conflicts, but sometimes you might need to explicitly exclude certain dependencies or specify a particular version. Check your pom.xml file for any conflicting dependencies and try to resolve them by excluding or specifying versions.

Another common issue is deployment failures. These can be caused by various reasons, such as incorrect configuration, missing dependencies, or errors in your application code. Check the WildFly server logs for any error messages. The logs are typically located in the standalone/log directory of your WildFly installation. Look for any exceptions or error messages that indicate the cause of the failure. Ensure that all required dependencies are included in your pom.xml file and that your application code is free of errors.

If you’re using the WildFly Maven plugin, make sure that the plugin is correctly configured and that the WildFly server is running. Check the plugin configuration in your pom.xml file and verify that the hostname, port, username, and password are correct. Try restarting the WildFly server and redeploying your application.

Another potential issue is related to Java version compatibility. Ensure that your project is configured to use a Java version that is supported by both WildFly and Jakarta EE 10. Check the maven-compiler-plugin configuration in your pom.xml file and verify that the source and target versions are set to a compatible Java version, such as Java 11 or later.

Finally, if you’re experiencing performance issues, consider optimizing your application code and WildFly configuration. Use profiling tools to identify any performance bottlenecks in your application. Optimize database queries, reduce the size of your WAR file, and tune the WildFly server configuration to improve performance. By addressing these common issues, you can ensure that your Jakarta EE 10 applications run smoothly and efficiently on WildFly with Maven.

By following this comprehensive guide, you should now be well-equipped to develop and deploy Jakarta EE 10 applications on WildFly using Maven. Happy coding, folks!