This list is not ordered, how important I feel these documents are really changed as I climbed up the learning curve. Suffice to say that each link here saved me weeks rather then days.

Getting Started

When starting out it is easy to get stuck in the details of how to accomplish things. These links not only help with that, but also provide some lasting understanding.

The Big Picture / Platform and Plug-ins

Notes on the Eclipse Plug-in Architecture

Article : A watershed document with a clear explanation about how an Eclipse application is assembled out of extension points and extensions.
learning what an extension point is good for
understanding lolly-pop diagrams
Comparision with Publish/Subscribe

Contributing to Eclipse Principles, Patterns and Plug-ins

Book : This book answers the crucial why questions I had about Eclipse development.
Buy for the UDIG:Eclipse House Rules
Buy if IAdaptable is bothering you
Some examples are showing their age
The last couple chapters that use patterns to show you how things work, and what trade-offs were considered, is worth the price of admission alone.

Rich Client Platform

Developing Eclipse Rich Client Applications

Tutorial : Makes use of the Eclipse wizards to make a quick intro. A good tutorial to check out while we wait for the other links to get updates.
Use of Wizards to limit writing of code
Intro to PDE Units
Predates the switch to Manifests (so you need to do a few extra steps to get your unit test to work)

Eclipse Rich Client Platform : Design, Coding, and Packaging Java (TM) Applications

review
I have a copy of it, I read it from cover to cover and I agree with this review…
Alain Demers, Faune Québec

Reference

For day to day day UDIG development you will find the following useful.

Development

Eclipse 3.1 Documentation

Website : I often find myself following outdated tutorials and using the online help system to see how things are done today.
From within Eclipse: Help > Help Contents
This is the only information that is actually up to date.
Use the website to provide links for others
Often can only be understood after you have figured it out

Offical Eclipse 3.0 FAQs

Book & Website : Quite helpful with the initial frustration of working with the Eclipse Framework. Helps when you just want it to work and don't care why.
Buy: if you use the above link more then twice an hour
Can be installed as a plug-in
The detailed code tips don't age well
I am going to buy the next version, not that we know when/if it is to be expected.

Building Commercial Quaility Plug-ins

Book : Despite its title, and perhaps intent, this book covers a great middle ground between the the Contributing to and the FAQ books. Covers a range of topics, communicating the tricks that we would not have found otherwise.
SWT Layout tutorial with the same form done with each layout manager
Was how I finally learned how to use Viewers, LabelDirectors and ItemProviders
Only book intro to building offline with PDE Build / Ant
Content occasionally needs adapting for RCP use
The main benefit to us was that it showied the use of these technologies for real. I would really recommend this book as an alternative to the FAQ book if you can make it through the first month without being annoyed at your ability to update a status bar.

SWT & JFace

SWT: The Standard Widget Toolkit, Volume 1

Book : A good reference (but so is the source code), I found the Building Commercial Quaility Plug-ins examples of using the SWT/JFace in anger more compelling.
Least used of all the books we bought

Editors and Views

Help system

Arcane & Advanced

If you wander into the guts of uDig development the following will be of service.

Eclipse Modeling Framework (EMF)

Eclipse Modeling Framework

Book : Eclipse Modeling Framework seems to be the first successful Model Driven Design framework. It uses a Ecore for modeling, a reduced subset of the UML2 Meta Object Facility (MOF).
Buy if you need to patch the core of the uDig application - Project, Map, Page etc..
Look into it for your own needs, it seems to be stupidly useful
IAdaptable is used instead of traditional listeners/events
It literally appears the be the shape of the future as the OMG is targeting the same subset w/ their EMOF work.

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