Wiki Issues

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A ROS 2 library for Java. Uses Fast-DDS middleware. Fully compatible with other supported ROS 2 middlewares.

Fast-DDS version: 3.2.2

ROS 2 compatible and tested distros: [humble, jazzy]

Supported platforms:

• Linux (Ubuntu 20.04+ or similar x86_64, arm64)
• Windows (Windows 10+ x86_64)
• (soon) macOS (macOS 13+ Intel, Apple Silicon)
• (soon) Android

Features

• Fully compatible with ROS 2 humble or newer (may also work with older ROS 2 distros)
• Does not require a ROS 2 installation on the system
• Ready-to-use Java library, just add to your Maven or Gradle dependencies!
• Publish and subscribe to ROS 2 topics
• Supports custom message types
• Generate Java classes from ROS 2 .msg files
• Fast-DDS backend
• Minimal and fast implementation
• Fully thread-safe
• Async and allocation-free API
• (soon) ROS 2 services
• (soon) ROS 2 actions
• (soon) ROS 2 parameters

Usage

Read in-depth documentation on the Wiki!

Here's the basics:

Create a ROS2Node:

int domainId = 100;
ROS2Node node = new ROS2Node("my_node", domainId); // domainId is 0 by default
// Call node.close() when you're done with the node!

Create a ROS2Topic:

ROS2Topic<Int32> intTopic = new ROS2Topic("/int_topic", Int32.class);

Create a ROS2Publisher and publish a message on the intTopic:

ROS2Publisher<Int32> intPublisher = node.createPublisher(intTopic);
Int32 message = new Int32();
message.setData(123);
intPublisher.publish(message);

Create a subscription to the intTopic:

ROS2Subscription<Int32> subscription = node.createSubscription(intTopic, reader -> {
  Int32 message = reader.read();
  // Do something with the message!
};

Talker and listener example

Run a talker and listener example with ./run_talker_listener.sh. If you have a local ROS 2 installation or use a ROS 2 container, you can verify that ROS 2 is able to communicate with jros2.

[New shell]
jros2$ ./run_talker_listener.sh
> Task :examples:ros2-ros2-talker-listener:run
Publishing: 'Hello world: 0'
Publishing: 'Hello world: 1'
I heard: 'Hello world: 1'
Publishing: 'Hello world: 2'
I heard: 'Hello world: 2'
[...]

[New shell]
jros2$ source /opt/ros/humble/setup.bash 
jros2$ ros2 topic echo /chatter
data: 'Hello world: 1'
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data: 'Hello world: 2'
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[...]