Use RXJava for Merging Response of 2 API calls

RxCombineApiCalls

Observable.combineLatest(
    ApiProvider.requestSource1(param1),
    ApiProvider.requestSource2(param2),
            this::combinedResponses)
            .map(responseObject -> saveResponse(responseObject, context))
            .subscribeOn(Schedulers.io())
            .observeOn(AndroidSchedulers.mainThread())
            .subscribe(responseObject -> onResponseReceived(responseObject, listener),
                      null != errorCallback ? errorCallback : this::onFetchObjectFailed);

Is the response from ApiProvider.requestSource1() and ApiProvider.requestSource2() the same or different?

Also this is where the observable that is omitted is a single source. For a list of data you would have to iterate over each source which is what I am trying to avoid. What I was looking at was having an iterable observable and merging the two data types for it.

The 2 responses are different. In my example, I'm sending the response "responseObject" from "source 1" into the map so that it can be used by the callback of "source 2" once the latter returns successfully. My use case was that I needed to merge the 2nd response with the results of the first 1 into a single object.