Another option to reach all datasource defined within a view is
List<Datasource> dataSourceList=((com.ibm.xsp.component.UIViewRootEx2)(FacesContext.getCurrentInstance() .getViewRoot())).getData();
then you go further, get Xpages runtime object and get actual data
as followinf if your datasourc is a document (assuming that you only have one datasource defined in your xpages)
com.ibm.xsp.model.domino.wrapped.DominoDocument doc = (com.ibm.xsp.model.domino.wrapped.DominoDocument) dataSourceList.get[0].getDataObject();
doc.getItemValue("paramA");
a little bit add up is that FacesContext.getCurrentInstance() .getViewRoot() returns only JSF default viewRoot, and we can't access domino datasource through this viewroot, unless you cast it as com.ibm.xsp.component.UIViewRootEx2,
( domino ViewRoot )