Developer Documentation

From ApCoCoAWiki

The ApCoCoA 2.0 project is divided in two sub projects: The CoCoA Plugin and the CoCoA IDE based on Intellij.


The IDE is based on IntelliJ Community Edition ( The source code of the Intellij Community edition is available on Github. We cloned the original repository and modified some files in the python branch to make our own customized IDE(ApCoCoA). However the repository on which we are working now is available on bitbucket: We modified the following files in the IDE:

  • In the python/resources folder you we replaced the IDE logos with our own logo.
  • In python/python-community-ide-resources/resources/tips you can find the files to modify the product name, the help page etc.
  • In the same python/python-community-ide-resources/resources folder you can find the file (/idea/PyCharmCoreApplicationInfo.xml)

to edit the IDE informations. There is more one can customize. Please refer to the github page or to the intelliJ Platform SDK DevGuide

Building the IDE

After the the IDE is customized as wanted, the last step is to build the sources in order to obtain the IDE for windows, linux and mac as follows:

On ubuntu, a sudo apt-get install ant would be enough.

  • Increase the Java Heap size for ant: > export ANT_OPTS="-Xmx5g -

XX:-UseGCOverheadLimit" or use export _JAVA_OPTIONS=- Xmx5000m to set a maximum heap size of 5G for example. To make those changes permanent, you have to add those commands in the /etc/profile

  • cd to the folder python in the source and run the command ant -f

build.xml The build generates in the directory python/out/pycharm-ce three folders: dist.mac, dist.unix, which contain the builded IDEs for the different platforms.

The CoCoA Plugin

The CoCoA plugin is the part of the project which adresses everything that is specific to the CoCoA language such as the syntax highlighting, the interpreter, the interactive window, the CoCoA files recognition... The plugin is developped as a normal intellij Platform plugin, meaning it can be used in other intellij IDEs to make them recognize and interpret a CoCoA file. Intellij platforms provides interesting tutorials on plugin creation:, creating_plugin_project.html Our plugin project is located in bitbucket at

Plugin implementation

The plugin implementation has 3 packages: com.cocoaplugin.ide, com.cocoaplugin.psi, com.cocoaplugin.psi In this package you will find the logic about the Cocoa Parser for syntax highlighting, and all other logic related to the cocoa language itself. For more information about this topic please refer to the IntelliJ Platform SDK DevGuide here: . This package contains the logic to create a run configuration for cocoa. It is not very important for the plugin to work but with a run configuration someone can send a cocoa file to the interpreter without using the interactive windows or the cocoa window. IMPORTANT: if you are building the plugin for windows or another OS please make sure the INTERPRETER_PATH in the class CocoaRunConfigurationProducer of this package is correct for that OS. com.cocoaplugin.ide This package is the most important package of the project as here you have the logic for the interactive Window, the events “send to Cocoa”, “refresh cocoa” , as well as the multithreading used to separate the interpreter threads from the IDE thread in order to avoid blocking everything when cocoa is calculating. Let’s choose some important classes in this package and give a brief description of them:

  • CocoaProcessManager

This class is the class where we manage the cocoa interpreter process running in the background. Again make sure the right interpreter path for the targeted OS is given(line 32).

  • InterpreterThread

This class represents the thread which reads the results produced by cocoa. It listens to the standard output of the cocoa interpreter process and whenever there is a result available, it prints it back to the user in the cocoa output window.

  • SendToCocoa

This class is an Intellij action ( action_system/working_with_custom_actions.html?search=action ) When the user starts the action “send to cocoa” we get the text selection and write it to the input of the cocoa interpreter process, 3and later the result will be read by the InterpreterThread as explained above.

  • CocoaInteractiveWindow

This is the cocoa interactive window. It interacsts with the two other classes TerminalFilter and TerminalNavigationFilter.

  • CocoaToolWindow

This class is the window for the cocoa Outputs. For more about IntellIj ToolWindows, please refer again to the IntellIj IntelliJ Platform SDK DevGuide


ApCoCoA can be simply distributed using the files generated during the building process. But the plugin also have to be integrated in the final distribution file. For that, you have to build the plugin. In Intellij open the plugin project and go to “Build > Prepare module apcocoa_plugin for Deployment”. A jar file(apcocoa_plugin.jar) will be generated in the project directory. Finally, move that plugin file to the dist.[os]/plugins/apcocoa/lib/ you want to distribute. When ApCoCoA starts, we always check whether the user has a CoCoA interpreter in his or her system already. Otherwise we copy the cocoa interpreter to the user’s home directory. How this is done can be found in the file bin/ or bin/start.bat(windows) of the current ApCoCoA.