Page which is enable in closed user group is not detected by Page class

I got this to work - here is the OUTPUT:

5.05.2016 16:10:28.478 *INFO* [0:0:0:0:0:0:0:1 [1462479028291] GET /content/SlingQuery.html HTTP/1.1] com.community.aem.impl.QueryImp **** CUG Child pages are: /content/geometrixx/en/toolbar/contacts/Test1
05.05.2016 16:10:28.478 *INFO* [0:0:0:0:0:0:0:1 [1462479028291] GET /content/SlingQuery.html HTTP/1.1] com.community.aem.impl.QueryImp **** CUG Child pages are: /content/geometrixx/en/toolbar/contacts/Test2
05.05.2016 16:10:28.478 *INFO* [0:0:0:0:0:0:0:1 [1462479028291] GET /content/SlingQuery.html HTTP/1.1] com.community.aem.impl.QueryImp **** CUG Child pages are: /content/geometrixx/en/toolbar/contacts/Test3
05.05.2016 16:10:28.478 *INFO* [0:0:0:0:0:0:0:1 [1462479028291] GET /content/SlingQuery.html HTTP/1.1] com.community.aem.impl.QueryImp **** CUG Child pages are: /content/geometrixx/en/toolbar/contacts/Test4
05.05.2016 16:10:28.478 *INFO* [0:0:0:0:0:0:0:1 [1462479028291] GET /content/SlingQuery.html HTTP/1.1] com.community.aem.impl.QueryImp **** CUG Child pages are: /content/geometrixx/en/toolbar/contacts/Test5

Here is the pages that belong to a CUG:

They belong to a CUG named membersonly. See: 

Notice that a System user (not an AEM USER) named datacug belongs to this group. 

Now we map the System user to the OSGI bunlde using Sling Mapping: 

Now you can use the System user you configured in Sling Mapping to access the CUG Pages in the Java code-- see: 

package com.community.aem.impl;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
  
  
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
  
import java.io.StringWriter;
import java.util.Iterator;
import java.util.List;
import java.util.ArrayList;
import java.util.HashMap; 
import java.util.Map; 
  
import javax.jcr.Repository; 
import javax.jcr.SimpleCredentials; 
import javax.jcr.Node; 
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
   
import org.apache.jackrabbit.commons.JcrUtils;
  
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
  
import org.apache.felix.scr.annotations.Component;
import org.apache.felix.scr.annotations.Service;
import javax.jcr.RepositoryException;
import org.apache.felix.scr.annotations.Reference;
import org.apache.jackrabbit.commons.JcrUtils;
  
import javax.jcr.Session;
import javax.jcr.Node; 
import com.community.aem.*; 
 
 //Sling Imports
import org.apache.sling.api.resource.ResourceResolverFactory ; 
import org.apache.sling.api.resource.ResourceResolver; 
import org.apache.sling.api.resource.Resource; 
import com.day.cq.wcm.api.Page; 
import com.day.cq.wcm.api.PageFilter; 
 
//This is a component so it can provide or consume services
@Component
 
  
@Service
public class QueryImp implements Query {
 
//Inject a Sling ResourceResolverFactory
    //Inject a Sling ResourceResolverFactory
    @Reference
    private ResourceResolverFactory resolverFactory;
    
    /** Default log. */
    protected final Logger log = LoggerFactory.getLogger(this.getClass());
     
@Override
public String getJCRData(String location) {
    
    
    Map<String, Object> param = new HashMap<String, Object>();
    param.put(ResourceResolverFactory.SUBSERVICE, "datacug");
    
      
    try {
                 
        
        //Get the title of the AEM web page at this specific location - assume its a value such as /content/geometrixx/en/services
         ResourceResolver resourceResolver = resolverFactory.getServiceResourceResolver(param);
         Resource res = resourceResolver.getResource(location);
        
        
                     
    //Adapts the resource to another type - in this example to a     com.day.cq.wcm.api.page
Page page = res.adaptTo(Page.class);

String title = page.getTitle(); // Get the title of the web page

//Write out the CUG Pages - the user datacug belongs to the UCG that has access to these pages 
Iterator<Page> it = page.listChildren() ;

while (it.hasNext()) {
    
    String name = (String) it.next().getPath(); 
    log.info("**** CUG Child pages are: "+name);
}

return title ; 
}
catch (Exception e)
{
    e.printStackTrace()  ; 
}
         
return null;
    }
 
}

There is a lot here - we will get this into a HELPX article - how to use SLING APIS to query pages that belong to a CUG. 

Also - as mentioned by Joerg and Lokesh - you cannot do this without using a System user who belongs to the group.