List depency changeset for a given changeset

In RTC 5.0 we added a "fill the gap" feature where the change sets that fill the gap are shown to the user, allowing them to either accept all the change sets or to continue with the gap workflow that was available in RTC 4.0.5.
This feature is summarized in the RTC 5.0 'New & Noteworthy' page: https://jazz.net/downloads/rational-team-concert/releases/5.0?p=news#eclipse-fill-gaps

The classes that are involved for filling the gap include:
client side: IWorkspaceConnection.findChangeSetsToAcceptToFillGap(...)
server side: IScmQueryService.findChangeSetsToAcceptToFillGap(...)

Gaps are explained in more detail in the "Improved Gap Handling for SCM" article: https://jazz.net/library/article/1372

No, there is no API that provides this info. I imagine the code would involve a lot of searching in the repository that would be quite intensive.

This is work item Provide GAP filling APIs (16842) .   It is not currently in-plan, so feel free to add a comment indicating your interest/support.   A GUI-level version of this request (there are several) is: "Confirm Content Accept" dialog should be more specific (offer to fill in gaps when a gap exception occurs) (24822)

One workaround that I placed in my solution is as Follows.

Assuming Dependent change sets are the change sets that either to be delivered at once together. That happens if any descendent change set present having same file in that.

So what I search for an particular change set is all Descendent change sets that is having same Item ID. and list down each of them.