ActiveJ: A Modern Java Platform Built From The Ground Up

Introduction

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 :

• Async.io - 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 {
    @Provides
    AsyncServlet servlet() {
        return request -> HttpResponse.ok200().withPlainText("Hello, World!");
    }

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

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 https://activej.io 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: https://github.com/activej/activej
License: Apache-2.0 license

#java #microservice

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