Java 11+ ships with a new HttpClient

To fetch the content of a website synchronously into a String:

import java.io.IOException;
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse.BodyHandlers;

...a request has to be constructed with an URI:

var uri = URI.create("https://airhacks.tv");
var request = HttpRequest.newBuilder(uri).GET().build();

...then sent (=executed) with an instance of HttpClient:

var client = HttpClient.newHttpClient();
String responseBody = client.send(request, BodyHandlers.ofString()).body();
System.out.println(responseBody);

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Building a frontend with vanilla Web Components for a "Kickass Java Backend"

GitHub's Time Elements: https://github.com/github/time-elements is a set of web components which comes without any dependencies, does not require any processing and is useful for formatting time and dates:

Building, designing, and structuring a cloud-native MicroProfile (Metrics, OpenAPI, FaultTolerance, JAX-RS, Config, Health, JSON-B, REST Client and JAX-RS) / Quarkus application. AWS / EKS / Kubernetes deployment included:

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Migration of an 8 years old Java EE 6 / Java 6 application written on stage of the JDD 2012 (Java EE: Future Is Now, But It Is Not Evenly Distributed Yet) conference to Jakarta EE 9 with the new jakarta.* packages.

GlassFish 6 was used as an example Jakarta EE 9 runtime:

Past, present and possible future of Java backends and Web frontends:

• Eclipse MicroProfile "umbrella" spec: spec html
• Configuration for MicroProfile: spec html | javadoc
• Eclipse MicroProfile Fault Tolerance: spec html | javadoc
• Eclipse MicroProfile Health: spec html | javadoc
• Eclipse MicroProfile JWT Authentication: spec html | javadoc
• Eclipse MicroProfile Metrics: spec html | javadoc
• Eclipse MicroProfile OpenAPI: Spec pdf | javadoc
• Eclipse MicroProfile OpenTracing: spec html | javadoc
• Eclipse MicroProfile Rest Client: spec html | javadoc

MicroProfile also relies on Java EE 8 APIs. The specs from the opensource Java EE 8 counterpart: Jakarta EE 8 are easier (directly) accessible:

• Jakarta Contexts and Dependency Injection: spec html | javadoc
• Jakarta Annotations: spec html javadoc
• Jakarta RESTful Web Services: spec html | javadoc
• Jakarta JSON Binding Specification: spec html | javadoc
• Jakarta JSON Processing: spec html | javadoc

Reactive Messaging for MicroProfile API allows mapping of method's parameters and return values to virtual channels:

import org.eclipse.microprofile.reactive.messaging.Incoming;
import org.eclipse.microprofile.reactive.messaging.Outgoing;

public class HelloListener {

    @Incoming("hello")
    @Outgoing("confirmed")
    public String onHello(String hello) {
        return "confirmed: " + hello;
    }
}    

Messages consumed by Jakarta RESTful Web Services / Java API for RESTful Web Services can be ingested into the system with the injected Emitter qualified with the @Channel annotation.

After sending the String to the Emitter, the message becomes available in the channel and can be consumed as method parameter or sent to Kafka topic:

import javax.inject.Inject;
import javax.ws.rs.Consumes;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.core.MediaType;

import org.eclipse.microprofile.reactive.messaging.Channel;
import org.eclipse.microprofile.reactive.messaging.Emitter;

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

    @Inject
    @Channel("hello")
    Emitter<String> emitter;

    @POST
    @Consumes(MediaType.TEXT_PLAIN)
    public void forward(String message) {
        emitter.send(message);
    }
}    

See it in action, and from scratch in 7 minutes: