Build in dashing version failed,in Ubuntu 18.0.4

[year112]

In README.md
mkdir -p ament_ws/src cd ament_ws curl -skL https://raw.githubusercontent.com/esteve/ament_java/master/ament_java.repos -o ament_java.repos vcs import src < ament_java.repos src/ament/ament_tools/scripts/ament.py build --symlink-install --isolated
and
mkdir -p ros2_java_ws/src cd ros2_java_ws curl -skL https://raw.githubusercontent.com/esteve/ros2_java/master/ros2_java_desktop.repos -o ros2_java_desktop.repos vcs import src < ros2_java_desktop.repos . ../ament_ws/install_isolated/local_setup.sh ament build --symlink-install --isolated
ament_java.repos and ros2_java_desktop.repos is out of date in 2018 .
When i build in dashing version ,there has too many mistakes.

how can i fix it？ by the way ，when you will maintain the latest version of the instructions（dashing 2020 or 2019）

[nielstiben]

I experienced similar issues. Have you tried cloning the dashing branch instead of the master branch?

Replace curl -skL https://raw.githubusercontent.com/esteve/ros2_java/master/ros2_java_desktop.repos -o ros2_java_desktop.repos
with curl -skL https://raw.githubusercontent.com/esteve/ros2_java/dashing/ros2_java_desktop.repos -o ros2_java_desktop.repos

[wilcobonestroo]

When I did the steps described by @nielstiben I ended up with two packages that could not build: rcljava_examples and test_msgs. The issue with test_msgs can be solved with #100 I can now build everything except for the examples with ament build --skip-packages rcljava_examples --symlink-install --isolated

[wilcobonestroo]

When I try to build jcljava_examples from the ros2_alpha8 branch, the error I get is

/home/ros/ros2_java_ws/build_isolated/rcljava_examples/src/main/java/org/ros2/rcljava/examples/Talker.java:18: error: cannot find symbol
import org.ros2.rcljava.Node;
                       ^ 

So, it seems that including the jcljava packages is not going well. At least, it can't find Node. I don't have much experience with Gradle, so I don't know how to solve this yet. Where can I update the settings for rcljava_examples so it can find the rcljava packages?

Edit: the include must be org.ros2.rcljava.node.Node;

Edit2: In the master branch, the above issues are solved. However, I get the error:

/home/ros/ros2_java_ws/src/ros2_java/ros2_java_examples/rcljava_examples/src/main/java/org/ros2/rcljava/examples/service/AddTwoIntsService.java:26: error: package example_interfaces.srv does not exist
      final example_interfaces.srv.AddTwoInts_Request request,
                                  ^

It doesn't know example_interfaces or example_interfaces.srv. What is this example_interfaces? Is it a class, variable, package? It looks like a package name, but where is it defined or where does it come from?

[wilcobonestroo]

@esteve I also see the example_interfaces.srv in your ROSCon presentation. However, I don't understand where it is defined. Can you help us with the questions above?

[wilcobonestroo]

@nielstiben If you delete the "addTwoInts" java files, then the other examples build. The subscriber_lambda and publisher_lambda work. With a little change also the subscriber_node and the publisher_node work.

[esteve]

@wilcobonestroo ros2_alpha8 branch is an old branch that predates the first official version of ROS 2, so it's not meant to be used, I've just removed it. The latest ROS 2 distro supported on master is Bouncy, but @jacobperron is working on adding support for Dashing and Eloquent in https://github.com/ros2-java/ros2_java/tree/dashing

[wilcobonestroo]

Thank you for your answers. Can you also give a hint about where example_interfaces.srv is defined? Once that error is fixed, the dashing version will build.

[jacobperron]

See #101 for adding example_interfaces to the repos file.

[jacobperron]

Dashing is EOL. Please try out the main branch with ROS Galactic.