Chapter 8 of Contributing to Eclipse - Principles, Patterns, and Plug-Ins begins, some people feel that it is too difficult to set the extension point, but not the case. Swiss children's first day will learn to slide and follow. Then slide this is not scary. So the author tends to discuss EXTENSION POIN early. This truth is actually universal. MIT insists that this classic is a big decision to introduce a book of undergraduate CS students.