The following describes how to set up a Processing tool project in Eclipse and build it successfully, and to make your tool ready for distribution.

Import to Eclipse

There are two options to import the template project into Eclipse: using a Git fork or using a downloaded package. If you are not familiar with Git or GitHub, you should opt for the downloaded package.

Option A: GitHub

1. Fork the template repository to use as a starting point.

• Navigate to https://github.com/processing/processing-tool-template in your browser.
• Click the "Fork" button in the top-right of the page.
• Once your fork is ready, open the new repository's "Settings" by clicking the link in the menu bar on the right.
• Change the repository name to the name of your tool and save your changes.
• NOTE: GitHub only allows you to fork a project once. If you need to create multiple forks, you can follow these instructions.

1. Clone your new repository to your Eclipse workspace.

• Open Eclipse and select the File → Import... menu item.
• Select Git → Projects from Git, and click "Next >".
• Select "URI" and click "Next >".
• Enter your repository's clone URL in the "URI" field. The remaining fields in the "Location" and "Connection" groups will get automatically filled in.
• Enter your GitHub credentials in the "Authentication" group, and click "Next >".
• Select the master branch on the next screen, and click "Next >".
• The default settings on the "Local Configuration" screen should work fine, click "Next >".
• Make sure "Import existing projects" is selected, and click "Next >".
• Eclipse should find and select the processing-tool-template automatically, click "Finish".

1. Rename your Eclipse project.

• In the Package Explorer, right-click (ctrl-click) on the folder icon of the processing-tool-template project, and select Refactor → Rename... from the menu that pops up.
• Give the project the name of your tool, and click "OK".

Option B: Downloaded Package

1. Download the latest Eclipse template from here. Don't unzip the ZIP file yet.
2. Create a new Java project in Eclipse.

• From the menubar choose File → New → Java Project.
• Give the project the name of your tool.
• Click "Finish".

1. Import the template source files.

• Right-click (ctrl-click) onto the folder icon of your newly created project in the Package Explorer and select "Import..."`" from the menu that pops up.
• Select General → Archive File, and click "Next >".
• Navigate to the ZIP file you downloaded earlier in step 1, and click "Finish".

Set Up and Compile

1. Add Processing to the project build path.

• Open your project's "Properties" window.
• Under "Java Build Path", select the "Libraries" tab and then "Add External JARs...".
• Locate and add Processing's pde.jar to your build path. If you're planning on using features of Processing's PApplet class, you'll need to add core.jar to the project's build path as well. It is recommended to make copies of core.jar and pde.jar in your Eclipse workspace in a libs folder. If this folder does not exist yet, create it. Read the section below regarding where to find the core.jar and pde.jar files.
• Confirm the setup with "OK".

1. Edit the tool properties.

• Open the resources folder inside of your Java project and double-click the build.properties file. You should see its contents in the Eclipse editor.
• Edit the properties file, making changes to items 1-4 so that the values and paths are properly set for your project to compile. A path can be relative or absolute.
• Make changes to items under 5. These are metadata used in the automatically generated HTML, README, and properties documents.

1. Compile your tool using Ant.

• From the menu bar, choose Window → Show View → Ant. A tab with the title "Ant" will pop up on the right side of your Eclipse editor.
• Drag the resources/build.xml file in there, and a new item "ProcessingTools" will appear.
• Press the "Play" button inside the "Ant" tab.

1. BUILD SUCCESSFUL. The tool template will start to compile, control messages will appear in the console window, warnings can be ignored. When finished it should say BUILD SUCCESSFUL. Congratulations, you are set and you can start writing your own tool by making changes to the source code in folder src.
2. BUILD FAILED. In case the compile process fails, check the output in the console which will give you a closer idea of what went wrong. Errors may have been caused by

• Incorrect path settings in the build.properties file. Things are most likely to go wrong at item 2, where you specify the path to pde.jar and other included JARs.
• Error "Javadoc failed". If you are on Windows, make sure you are using a JDK instead of a JRE in order to be able to create the Javadoc for your tool. JRE does not come with the Javadoc application, but it is required to create tools from this template.

After having compiled and built your project successfully, you should be able to find your tool in Processing's sketchbook folder, examples will be listed in Processing's sketchbook menu. Files that have been created for the distribution of the tool are located in your Eclipse's workspace/yourProject/distribution folder. In there you will also find the web folder which contains the documentation, a ZIP file for downloading your tool, a folder with examples as well as the index.html and CSS file.

To distribute your tool please refer to the Tool Guidelines.

Source code

If you want to share your tool's source code (and we know you do), we recommend using an online repository available for free at GitHub.

Adding pde.jar and other .jar files to your classpath

The pde.jar file contains classes responsible for creating the Processing Development Environment itself. It must be part of your classpath when building a tool. The core.jar file does not necessarily need to be added to your classpath, however, you will need to include it if you plan on creating any external tool windows based on PApplet. On Windows and Linux, these files are located in the Processing distribution folder inside a folder named "lib". On Mac OS X, right-click Processing.app and use Show Package Contents to see the guts. The lib folder is at Contents → Resources → Java → lib. For further information about the classes in pde.jar, you can see the source here and the developer documentation here.

If you created a libs folder as described above, put the libraries you need to add to your classpath in there. In the Properties of your Java project, navigate to Java Build Path → Libraries, and click Add External JARs. Select the .jar files from the libs folder that are required for compiling you project. Adjust the build.properties file accordingly.

The libs folder is recommended but not a requirement, nevertheless you need to specify where your jar files are located in your system in order to add them to the classpath.

In case a tool depends on systems libraries, put these dependencies next to the jar file. For example processing's opengl.jar library depends on JOGL hence the DLLs (for Windows) or jnilibs (for OS X) have to be located next to the opengl.jar file.

The JDK, the JRE, Ant, & javadoc

For more information about these, see the relevant sections in the Eclipse Library Template README.