JAX-RS 3 API Server with Jetty 11

Here is a basic server setup with JAX-RS 3 using Jersey and Jetty 11 for the server. JAX-RS is Java API specification for RESTful web services using annotations. The project structure is as follows.

APIZenServer
├── src
│   └── main
│       └── java
│           └── net
│               └── jsloop
│                   └── apizen
│                       ├── APIZenServer.java
│                       ├── HealthResource.java
│                       └── MainResource.java
└── pom.xml

// APIZenServer.java

package net.jsloop.apizen;

import org.eclipse.jetty.server.Server;
import org.eclipse.jetty.server.ServerConnector;
import org.eclipse.jetty.servlet.ServletContextHandler;
import org.eclipse.jetty.servlet.ServletHolder;
import org.glassfish.jersey.servlet.ServletContainer;

public class APIZenServer {
    public static void main(String[] args) {
        Server server = new Server();
        ServerConnector connector = new ServerConnector(server);
        connector.setHost("0.0.0.0");
        connector.setPort(8080);
        server.addConnector(connector);

        ServletContextHandler context = new ServletContextHandler(ServletContextHandler.SESSIONS);
        context.setContextPath("/");

        ServletHolder jerseyServlet = context.addServlet(ServletContainer.class, "/*");
        jerseyServlet.setInitOrder(0);
        jerseyServlet.setInitParameter(
                "jersey.config.server.provider.classnames",
                String.join(",",
                        HealthResource.class.getCanonicalName(),
                        MainResource.class.getCanonicalName()
                )
        );

        server.setHandler(context);

        try {
            server.start();
            System.out.println("Server running at http://0.0.0.0:8080");
            System.out.println("Health check: http://0.0.0.0:8080/health");
            server.join();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            server.destroy();
        }
    }
}

// HealthResource.java

package net.jsloop.apizen;

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

@Path("/")
public class HealthResource {
    @GET
    @Path("/health")
    @Produces(MediaType.APPLICATION_JSON)
    public Response getHealth() {
        return Response.ok("{\"status\": \"true\", \"health\": \"ok\"}").build();
    }
}

// MainResource.java

package net.jsloop.apizen;

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

@Path("/")
public class MainResource {
    @GET
    @Path("/")
    @Produces(MediaType.APPLICATION_JSON)
    public Response getRoot() {
        return Response.ok("{\"status\": \"ok\"}").build();
    }
}

<!-- pom.xml -->

<?xml version="1.0" encoding="UTF-8"?>
<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>net.jsloop</groupId>
    <artifactId>APIZen</artifactId>
    <version>1.0</version>
    <packaging>jar</packaging>

    <properties>
        <maven.compiler.source>21</maven.compiler.source>
        <maven.compiler.target>21</maven.compiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <jersey.version>3.1.10</jersey.version>
        <jetty.version>11.0.25</jetty.version>
    </properties>

    <dependencies>
        <!-- Jersey -->
        <dependency>
            <groupId>org.glassfish.jersey.containers</groupId>
            <artifactId>jersey-container-jetty-servlet</artifactId>
            <version>${jersey.version}</version>
        </dependency>
        <dependency>
            <groupId>org.glassfish.jersey.inject</groupId>
            <artifactId>jersey-hk2</artifactId>
            <version>${jersey.version}</version>
        </dependency>
        <dependency>
            <groupId>org.glassfish.jersey.media</groupId>
            <artifactId>jersey-media-json-binding</artifactId>
            <version>${jersey.version}</version>
        </dependency>

        <!-- Jetty -->
        <dependency>
            <groupId>org.eclipse.jetty</groupId>
            <artifactId>jetty-server</artifactId>
            <version>${jetty.version}</version>
        </dependency>
        <dependency>
            <groupId>org.eclipse.jetty</groupId>
            <artifactId>jetty-servlet</artifactId>
            <version>${jetty.version}</version>
        </dependency>

        <!-- Logging -->
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-simple</artifactId>
            <version>2.0.12</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-assembly-plugin</artifactId>
                <version>3.6.0</version>
                <configuration>
                    <archive>
                        <manifest>
                            <mainClass>net.jsloop.apizen.APIZenServer</mainClass>
                        </manifest>
                    </archive>
                    <descriptorRefs>
                        <descriptorRef>jar-with-dependencies</descriptorRef>
                    </descriptorRefs>
                </configuration>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <goals>
                            <goal>single</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>

We can run this direclty from IntelliJ or from command line. For command line, follow the below steps.

mvn clean package
java -jar target/APIZen-1.0-jar-with-dependencies.jar

The server has two endpoints. One the root / and another /health which returns a JSON response. The /health endpoint is accessible at http://localhost:8080/health and returns {"status": "true", "health": "ok"}.