For example, when you click on any HTML anchor element <a>, you can code it to open the link in the same window, or have it open in a separate window using the HTML attribute: target="_blank"
Does h:commandButton have this kind of attribute? No.
What else does it have? It has an "action" attribute. Would that work? Possibly. What about the HTML attributes "onclick" ?
Assuming you already know how to work with the PDF and Crystal Reports APIs, there are several ways to go about opening new browser windows. They either require Javascript or your PDF/Crystal pages to be
Servlets accessible via a URL.
My opinion is this sounds like poor design, having one button open two other windows, but, everyone has different opinions.
Recall that when you use the action attribute of a h:commandButton in JSF, you are setting a
string value explicitly, or returning a string value from a method binding, used for page navigation.