Actionlib for Rosjava

A pure java implementation of actionlib for rosjava.

Key Features:

1. Easy developing and testing in any OS (Windows, Linux, Mac) without a ROS installation.
2. Compatible and usable with ROS. Tested with ROS Indigo.
3. Uses Log4j2 and SL4J
4. Smaller public API, with all the needed functionality plus some extras.
   • The API favours composition based designs and prevents inheriting the project classes. Where possible classes and methods are marked with the final modifier to prevent extension.
   • Includes separate ActionClientResult, ActionClientStatus and ActionClientFeedbackListener as well a complete ActionClientListener
   • ActionClient can accept multiple simultaneous Client listeners of different types, that can also be removed
   • The public methods and API includes only required elements. Only needed classes and methods are public.
   • Refactored code, grouping together common elements
5. Robust detection of started ActionServer in waitForActionServerToStart
6. Targeted to be used as part of other Java / ROS Java applications via gradle or maven, similar to other java libraries

Other Changes:

1. ActionClient only responds to messages for the same GoalId.
2. ActionClient will cancel a GoalId after receiving it, to allow the server to remove it from the GoalStatusArray
3. ActionClient can call a Runnable once and only if and when connected to the ActionLib protocol.

Requirements:

• Java 11 or greater (OpenJDK should work).
• For usage with a ROS installation the following packages:
  • are needed in runtime: ros-$ROS_DISTRO-actionlib ros-$ROS_DISTRO-genjava
  • could be helpful for testing/development: ros-$ROS_DISTRO-actionlib-tutorials

Downloading:

TODO

Building

The project will be compiled and tested in any OS (Windows, Linux, Mac) without any requirement for a ROS installation. Instructions are provided hereafter for Windows and Linux.

Windows Power Shell

1. Clone the project repository: git clone https://github.com/SpyrosKou/rosjava_actionlib.git

2. Go into the cloned repository directory: cd .\rosjava_actionlib\

3. Build the project. .\gradlew.bat build

4. Running the Unit tests. The tests will run during the build, but the following command can run the tests on demand. .\gradlew.bat test

Linux

1. Clone the project repository: git clone https://github.com/SpyrosKou/rosjava_actionlib.git

2. Go into the cloned repository directory: cd rosjava_actionlib/

3. Add execute permission to gradlew script: sudo chmod +x gradlew

4. Build the project. Tests will be executed automatically. ./gradlew build

5. Running the Unit tests. The tests will run during the build, but the following command can run the tests on demand. ./gradlew test`

Running a test client:

1. TODO

Using a Client

When an ActionClient invokes a server it returns an ActionFuture.

See an example client at FutureBasedClient .

The FutureBasedClient usage is demonstrated in FutureBasedClientTest.

Output from the test client

The test client will connect to the fibonacci server and send it a goal. It should then receive feedback from the server and a final response. The output should look something like this:

Loading node class: com.github.rosjava_actionlib.FibonacciActionLibClient

Waiting for action server to start...
Action server started.

Sending goal...
Sent goal with ID: /fibonacci_test_client-1-1453494018.17000000
Waiting for goal to complete...
Feedback from Fibonacci server: 0 1 1
Feedback from Fibonacci server: 0 1 1 2
Feedback from Fibonacci server: 0 1 1 2 3
Got Fibonacci result sequence: 0 1 1 2 3
Goal completed!

Sending a new goal...
Sent goal with ID: /fibonacci_test_client-2-1453494021.25000000
Cancelling this goal...
Feedback from Fibonacci server: 0 1 1
Got Fibonacci result sequence:
Goal cancelled succesfully.

Bye!

Running a test server:

1. TODO

Output from the test server

The test server will start running and wait for clients to connect and send goal messages. Once the fibonacci client sends a goal, the server accepts it and sends a result. The output should look something like this:

Goal received.
Goal accepted.
Sending result...

Running demos for the server and the client

You can launch a demo client and a fibonacci action server all at once using:

roslaunch rosjava_actionlib client_demo.launch --screen

You can also launch a demo server and a fibonacci action client all at once using:

roslaunch rosjava_actionlib server_demo.launch --screen

Use Ctrl+C to stop the execution once it's finished.

Motivation

TODO