/java-game-server

Jetserver is a high speed nio socket based multiplayer java game server written using Netty and Mike Rettig's Jetlang.It is specifically tuned for network based multiplayer games and supports TCP and UDP network protocols.

Primary LanguageJavaMIT LicenseMIT

Nadron is a Java NIO based server specifically designed for multiplayer games. It supports UDP and TCP transports. It uses Netty 4.1 for high speed network transmission and Jetlang for extremely fast in-VM message passing between player sessions and game rooms. The project uses Spring Framework 6 for dependency injection, making it highly configurable so you can swap out any part of the server with your own implementations.

Technology Stack

  • Java 17 LTS - Modern, long-term support release
  • Netty 4.1.115 - High-performance async network framework
  • Spring Framework 6.2.0 - Dependency injection and application context
  • Jackson 2.18.1 - JSON serialization
  • JUnit 5.11.3 - Modern testing framework
  • Log4j 2.24.2 - Secure, modern logging
  • SLF4J 2.0.16 - Logging abstraction

Wiki

The wiki provides implementation level details and answers to general questions that a developer starting to use Nadron server might have about it. This blog post contains a decent tutorial on creating a multiplayer game using this server. Support Group

For general discussion please use the Nadron server google group. Issues and bugs can be raised directly in github.

Requirements

  • Java 17 or later - The project uses Java 17 LTS features
  • Maven 3.8+ - For building the project

Installation

Maven

<dependency>
    <groupId>com.github.menacher</groupId>
    <artifactId>nadron</artifactId>
    <version>0.8-SNAPSHOT</version>
</dependency>

Building from Source

Prerequisites:

  • Java 17 JDK or later
  • Maven 3.8 or later
  • Git

Steps:

  1. Clone the repository:

    git clone git@github.com:menacher/java-game-server.git
cd java-game-server/nadron

  2. Build the project:

    mvn clean install

  3. Run tests:

    # Run regular tests (excludes performance tests)
mvn test

# Run performance tests
mvn test -Pperformance

  4. The built JAR will be in target/nadron-0.8-SNAPSHOT.jar

IDE Setup

IntelliJ IDEA / Eclipse / VS Code:

  • Simply import as a Maven project
  • The IDE will automatically download dependencies
  • Make sure your project SDK is set to Java 17+

For Eclipse users:

mvn eclipse:eclipse

Then import the project via File → Import → Existing Projects into Workspace

Performance

The modernized Nadron server delivers excellent performance on Java 17:

  • Message passing rate: Up to 40+ million messages/sec between sessions
  • Event dispatching: 5 million events in ~0.6 seconds
  • Session communication: 10-40 million messages/sec depending on configuration

Testing

The project includes comprehensive unit tests using JUnit 5:

  • 13 regular tests - Fast unit tests that run with every build
  • 4 performance tests - Tagged separately for performance benchmarking

Happy coding!