How to get data from Impact Analysis tab ?

One answer

This is not an out of the box tab in EWM - it's a custom one that's been built by your organisation. You'll need to first identify the names of the fields that contain the data, then build the access.
If you're using Java then I would recommend you start with Eclipse Lyo, which will help you build OSLC apps. Otherwise the Plain Java Client API can be used, and Ralph Schoon has some awesome articles on how to do this on his blog site. He includes lots of details on how to set up your project and do all sorts of things using the API