| Note: This tutorial assumes that you have completed the previous tutorials: Anatomy of a RosJava Package, Creating Rosjava Packages. |
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To Build with Catkin or Gradle
Description: Explains when to use catkin_make and when to use the gradle wrapper.Keywords: rosjava
Tutorial Level: BEGINNER
This tutorial provides some information on the different build methods for rosjava packages - these are catkin_make and the gradle wrapper.
Overview
A typical workspace will look like (refer to anatomy of a rosjava package for more details):
/src
/rosjava_catkin_package_a
/rosjava_gradle_subproject_a
/rosjava_gradle_subproject_b
/rosjava_gradle_subproject_c
/rosjava_catkin_package_b
/rosjava_gradle_subproject_d
/rosjava_gradle_subproject_e
/rosjava_gradle_subproject_fThe best way of understanding the usefulness of both build commands is to understand their scope. In the above workspace, catkin_make has scope across the whole workspace - it is responsible for linking and sequencing each catkin package/gradle (super)project. The gradle wrapper on the other hand only has scope within a single catkin package.
When to Use Catkin Make
Catkin make is useful in the following situations:
- A first build of your entire workspace since it creates the setup.bash and is a one-shot way of building the entire workspace.
- Continuous integration builds.
If we didn't have catkin packages linking the gradle projects, you'd need to compile each by hand, one by one, or have a bash script to do so for you.
When to Use the Gradle Wrapper
You can use catkin_make exclusively, but that can be annoyingly slow as it's running through the entire workspace. Just as for c++ catkin builds (where you use make), you can drop down a level and directly use the gradle wrapper to compile single gradle projects, or even subprojects.
Compiling a binary app subproject:
> source devel/setup.bash > cd src/rosjava_catkin_package_a/my_pub_sub_tutorial > ../gradlew installApp
Compiling a library subproject:
> source devel/setup.bash > cd src/rosjava_catkin_package_a/my_java_library > ../gradlew publishMavenJavaPublicationToMavenRepository
