I’m working on an Eclipse plug in (basically it gets posts from social networks such as Facebook and Twitter). I have various plug-in projects and I have one of them which makes use of another. I include the latter project in my build path and it compiles OK. However when I run the projects (Run As – > Eclipse Application) I get a java.lang.ClassNotFoundException.
Previously I had a similar issue but I was referencing a JAR file so apart from including it in the build path, I included it in the classpath from the Runtime tab in Eclipse and it worked fine. However Eclipse only seems to allow JAR files and not plug-in projects in the workspace to be included in the classpath.
I’ve tried various ways to try to include the plug-in project I need but the java.lang.ClassNotFoundException still comes up.
You need to add the plugin you are using as a dependency of the plugin you are writing. Once that is setup open the Run Configuration for your project, click on the Plug-Ins tab and select the “Add Required Plugins” button.
See also this post.