What is the best way to build a Web Based EER diagram drawing tool?

I have to create a Web Based EER diagram designing tool for one of my projects. As a main feature I have to build a free object movable,re-sizable environment with drag and drop and drawing features. These features are somewhat similar to MySQL Workbench EER diagram drawing tool.

Is there any advanced JavaScript library other than JQuery UI to done this job easily?

or

Is there any other technology to done this easily by using another programming language?