use jointjs library to build a graph, it's a good library with very few documents.
http://jointjs.com/demos/fsa as above page, when mouse move on link, there is a 'remove' icon on link, which can be clicked to remove link, and I want to disable 'remove' action on links? please advise.
The easiest way is to set .link-tools .tool-remove { display: none }
in your CSS.