How to resolve pathfield of classic dialog that is used in jsp ?

<%
%><%@include file="/libs/foundation/global.jsp"%><%
%><%@page session="false" %><%
%><%

    String pagepath =  properties.get("rootPath", String.class);
    String mappath = null;

    if(pagepath!=null){
     mappath = slingRequest.getResourceResolver().map(pagepath);

}

  %><%=mappath%><%

%>

You need .content.xml associated with /etc/map as well -

<?xml version="1.0" encoding="UTF-8"?>

-<jcr:root sling:internalRedirect="[/content/we-retail]" jcr:primaryType="sling:Mapping" xmlns:jcr="http://www.jcp.org/jcr/1.0" xmlns:sling="http://sling.apache.org/jcr/sling/1.0">

<redirect/>

<reverse/>

</jcr:root>

<?xml version="1.0" encoding="UTF-8"?>
<jcr:root xmlns:sling="http://sling.apache.org/jcr/sling/1.0" xmlns:jcr="http://www.jcp.org/jcr/1.0"
    jcr:primaryType="sling:Mapping"
    sling:internalRedirect="[/content/we-retail/$1,/$1]"
    sling:match="(.+)$"/>

<?xml version="1.0" encoding="UTF-8"?>
<jcr:root xmlns:sling="http://sling.apache.org/jcr/sling/1.0" xmlns:jcr="http://www.jcp.org/jcr/1.0"
    jcr:primaryType="sling:Mapping"
    sling:internalRedirect="[/content/we-retail/(.*).html]"
    sling:match="$1/"/>

Please refer https://www.albinsblog.com/2018/04/how-to-implement-extension-less-urls-in-adobe-experience-manager.html#.Yoj1aKhBw2w for How to implement extension-less URL's in Adobe Experience Manager(AEM) implementation.

Hope this will help.