how to include external JS files in SAP EP

hi,

public class MyFirstView extends AbstractPortalComponent

{

    public void doContent(IPortalComponentRequest request, IPortalComponentResponse response)

    {   

    IResource js = request.getResource(IResource.SCRIPT, "scripts/export.js");

        response.include(request, js);

        IResource jsp = request.getResource(IResource.JSP, "jsp/home.jsp");

        response.include(request, jsp);

   }

}

contents of home.jsp

<form action="#" method="GET">

<input type="text"  name="lastName"/>

    <button type="submit" name="doAction">Search </button> <BR>

    <button  onclick="javascript:exportToFile();">Export Table data into Excel</button> <BR>

    </form>

exportToFile() function is present in export.js.

But the function is not getting called on button click ?

can anybody help me?