This is a basic tutorial on how to create a simple base eclipse plugin which will have extension-point defined and also creating another eclipse plugin which will have extension to hook to existing extension-point in base plugin.
this whole tutorial has two primary tasks and they are
1.Creating a base plugin having an extension point definition.
2.Creating an extension plugin which implements the base extension point.

Creating a base plugin having an extension point definition.
Now let's see how this base plugin will be created which will have definition to a extension-point.
Once after opening your eclipse in plug-in-development perspective, create a new project by name Base Plugin.
1. Create a new eclipse plugin project from File > New






6. Now modify the plugin.xml file in the project created to that custom menu names and sub menus will be displayed.
Modified plugin XML code looks like below ..