ActiveJ: A Modern Java Platform Built From The Ground Up


ActiveJ is a modern Java platform built from the ground up. It is designed to be self-sufficient (no third-party dependencies), simple, lightweight and provides competitive performance. ActiveJ consists of a range of libraries, from dependency injection and high-performance asynchronous I/O (inspired by Node.js), to application servers and big data solutions. You can use ActiveJ to build scalable web applications, distributed systems and use it for high-load data processing.

ActiveJ components

ActiveJ consists of several modules, which can be logically grouped into the following categories :

  • - High-performance asynchronous IO with the efficient event loop, NIO, promises, streaming, and CSP. Alternative to Netty, RxJava, Akka, and others. (Promise, Eventloop, Net, CSP, Datastream)
  • HTTP - High-performance HTTP server and client with WebSocket support. It can be used as a simple web server or as an application server. Alternative to other conventional HTTP clients and servers. (HTTP)
  • ActiveJ Inject - Lightweight library for dependency injection. Optimized for fast application start-up and performance at runtime. Supports annotation-based component wiring as well as reflection-free wiring. (ActiveJ Inject)
  • Boot - Production-ready tools for running and monitoring an ActiveJ application. Concurrent control of services lifecycle based on their dependencies. Various service monitoring utilities with JMX and Zabbix support. (Launcher, Service Graph, JMX, Triggers)
  • Bytecode manipulation
    • ActiveJ Codegen - Dynamic bytecode generator for classes and methods on top of ObjectWeb ASM library. Abstracts the complexity of direct bytecode manipulation and allows you to create custom classes on the fly using Lisp-like AST expressions. (ActiveJ Codegen)
    • ActiveJ Serializer - Fast and space-efficient serializers created with bytecode engineering. Introduces schema-free approach for best performance. (ActiveJ Serializer)
    • ActiveJ Specializer - Innovative technology to improve class performance at runtime by automatically converting class instances into specialized static classes and class instance fields into baked-in static fields. Provides a wide variety of JVM optimizations for static classes that are impossible otherwise: dead code elimination, aggressive inlining of methods and static constants. (ActiveJ Specializer)
  • Cloud components
    • ActiveJ FS - Asynchronous abstraction over the file system for building efficient, scalable local or remote file storages that support data redundancy, rebalancing, and resharding. (ActiveJ FS)
    • ActiveJ RPC - High-performance binary client-server protocol. Allows building distributed, sharded, and fault-tolerant microservice applications. (ActiveJ RPC)
    • Various extra services: ActiveJ CRDT, Redis client, Memcache, OLAP Cube, Dataflow

Quick start

Paste this snippet into your terminal...

mvn archetype:generate -DarchetypeGroupId=io.activej -DarchetypeArtifactId=archetype-http -DarchetypeVersion=5.2

... and open the project in your favorite IDE. Then build the application and run it. Open your browser on localhost:8080 to see the "Hello World" message.

Full-featured embedded web application server with Dependency Injection:

public final class HttpHelloWorldExample extends HttpServerLauncher {
    AsyncServlet servlet() {
        return request -> HttpResponse.ok200().withPlainText("Hello, World!");

    public static void main(String[] args) throws Exception {
        Launcher launcher = new HttpHelloWorldExample();

Some technical details about the example above:

  • The JAR file size is only 1.4 MB. By comparison, the minimum size of a Spring web application is about 17 MB.
  • The cold start time is 0.65 sec.
  • The ActiveJ Inject DI library used is 5.5 times faster than Guice and hundreds of times faster than Spring.

To learn more about ActiveJ, please visit or follow our 5-minute getting-started guide.

Examples of using the ActiveJ platform and all ActiveJ libraries can be found in the examples module.

Release notes for ActiveJ can be found here

Download Details:
Author: activej
Source Code:
License: Apache-2.0 license

#java #microservice

What is GEEK

Buddha Community

ActiveJ: A Modern Java Platform Built From The Ground Up
Tyrique  Littel

Tyrique Littel


How to Install OpenJDK 11 on CentOS 8

What is OpenJDK?

OpenJDk or Open Java Development Kit is a free, open-source framework of the Java Platform, Standard Edition (or Java SE). It contains the virtual machine, the Java Class Library, and the Java compiler. The difference between the Oracle OpenJDK and Oracle JDK is that OpenJDK is a source code reference point for the open-source model. Simultaneously, the Oracle JDK is a continuation or advanced model of the OpenJDK, which is not open source and requires a license to use.

In this article, we will be installing OpenJDK on Centos 8.

#tutorials #alternatives #centos #centos 8 #configuration #dnf #frameworks #java #java development kit #java ee #java environment variables #java framework #java jdk #java jre #java platform #java sdk #java se #jdk #jre #open java development kit #open source #openjdk #openjdk 11 #openjdk 8 #openjdk runtime environment

ActiveJ Java platform takes aim at Spring, Quarkus

High-performance Java platform born in ad-tech is geared toward high-load web, cloud, networking, and microservices applications

Positioned as a replacement for multiple Java technologies, the ActiveJ platform is being put forward as a minimalistic, boilerplate-free, and fast technology stack for web, cloud, microservices, and high-load applications.

Consisting of loosely coupled components for asynchronous processing, I/O processing, high-performance web serving, and high-performance networking, ActiveJ, from the company of the same name, was built to replace SpringSparkRed Hat QuarkusMicronautVert.x, and other Java frameworks.

#activej #activej java platform #spring #quarkus #activej java platform takes aim at spring, quarkus #activej java

Samanta  Moore

Samanta Moore


Going Beyond Java 8: Local Variable Type Inference (var) - DZone Java

According to some surveys, such as JetBrains’s great survey, Java 8 is currently the most used version of Java, despite being a 2014 release.

What you are reading is one in a series of articles titled ‘Going beyond Java 8,’ inspired by the contents of my book, Java for Aliens. These articles will guide you step-by-step through the most important features introduced to the language, starting from version 9. The aim is to make you aware of how important it is to move forward from Java 8, explaining the enormous advantages that the latest versions of the language offer.

In this article, we will talk about the most important new feature introduced with Java 10. Officially called local variable type inference, this feature is better known as the **introduction of the word **var. Despite the complicated name, it is actually quite a simple feature to use. However, some observations need to be made before we can see the impact that the introduction of the word var has on other pre-existing characteristics.

#java #java 11 #java 10 #java 12 #var #java 14 #java 13 #java 15 #verbosity

Samanta  Moore

Samanta Moore


Spring Boot and Java 16 Records

In this article, we will discuss Java 16’s newest feature, Records. Then we will apply this knowledge and use it in conjunction with a Spring Boot application.

On March 16th, 2021, Java 16 was GA. With this new release, tons of new exciting features have been added. Check out the release notes to know more about these changes in detail. This article’s focus will be on Java Records, which got delivered with JEP 395. Records were first introduced in JDK 14 as a preview feature proposed by JEP 359, and with JDK 15, they remained in preview with JEP 384. However, with JDK 16, Records are no longer in preview.

I have picked Records because they are definitely the most favored feature added in Java 16, according to this Twitter poll by Java Champion Mala Gupta.

I also conducted a similar survey, but it was focused on features from Java 8 onwards. The results were not unexpected, as Java 8 is still widely used. Very unfortunate, though, as tons of new features and improvements are added to newer Java versions. But in terms of features, Java 8 was definitely a game-changer from a developer perspective.

So let’s discuss what the fuss is about Java Records.

#java #springboot #java programming #records #java tutorials #java programmer #java records #java 16

Seamus  Quitzon

Seamus Quitzon


Learning by Doing: How to Learn Java Basics by Building Your Own Project

Java is not the hardest language to start with. So, it becomes way popular among novice developers joining the ranks of Java coders every single day. If you are reading this blog post, you might be interested in learning Java.

Java is widely used across industry, and especially in the area of Enterprise software, which results in many high paying job opportunities and makes this programming language a common language for newbies. A general promotion of it within colleges and other institutions providing a formal Computer Science education also contributes to its popularity.

However, these are not the only advantages of Java — among other things, it allows you to adopt good practices and makes it way easier to learn other languages in the future. And with no doubt, you can easily learn it if you’re following the right approach. In this post, I am going to share some of them with you.

The Importance of Practice in Programming

Beyond all doubt, practice is important and valuable. But, before we get to the advantages of hands-on experience, I want to draw your attention to one essential thing I often tell my students.

New programmers who are just learning and start implementing things, without being supervised, often end up adapting bad practices. To avoid that, especially when you are making your first steps in programming, I recommend looking for a person who will supervise you and teach you. A strong mentorship with someone engaged in a serious project, as well as communication within the community in the form of sharing code and asking for feedback, is worth the effort. Similarly, when you are applying for your first job, you want to be looking for a company with a strong team and a good leader who would be keen on investing into your learning.

Now, let’s return to practical experience. Learning by doing is different from learning by passively consuming the information. To make sure we can use all the newly acquired technology, we should put our skills to test and write tons of code. The benefits of hands-on experience are almost endless.

Efficiency and Productivity

By practicing, you get a clear understanding of what programming is. Consequently, you start doing better with each new hands-on task, complete it faster, and thus become more productive.

Even if you are not working on real-world projects yet, it’s important to get used to having deadlines. They are inextricably linked to the programming process. My recommendation is to set up your own deadlines while practicing stage and follow them as closely as possible.

#java #learn java #java code #learn java in easy way #learn java course #learn java development