Google's Auto Suggest is a best example for AJAX implementation. XMLHttp Request is the object that does the job behind the scene.
So finally deleted and re-created the project Close all open projects and exit Eclipse.
Now you can open Eclipse without getting the error.
After checking what could be happening I found that in Eclipse's progress tab there is a couple of endless tasks: These tasks seem to never end and makes my Eclipse unusable.
Error "An internal error occurred during: "Initializing Java Tooling". Null Pointer Exception" is gone and Eclipse just working good.
Documentation is provided with a collapsible index on the left side and HTML documentation on the right, and can be searched (thanks to the Apache Lucene search engine). For example, you can use JSPs to make your documentation change dynamically (though we will discuss later a possible reason to avoid doing this).
View image at full size Documentation is split into "books," and you can have as many books as you like in one instance of the help system.
I tried closing and re-opening the project which took care of this problem.
BUT I had other side-effects (CTRL SHIFT R did not get all files in the project).