public static XModelObject getJarEntryObject(IProject p, String jarFile, String entry) {
   if (p == null) {
     IFile f = EclipseResourceUtil.getFile(jarFile);
     if (f == null) return null;
     p = f.getProject();
   }
   if (p == null) return null;
   IModelNature n = EclipseResourceUtil.getModelNature(p);
   XModel model = null;
   if (n != null) {
     model = n.getModel();
   } else {
     XModelObject o = EclipseResourceUtil.createObjectForResource(p);
     if (o != null) model = o.getModel();
   }
   if (model == null) return null;
   XModelObject[] fs = FileSystemsHelper.getFileSystems(model).getChildren();
   for (XModelObject s : fs) {
     String loc =
         Paths.expand(s.get(XModelObjectConstants.ATTR_NAME_LOCATION), model.getProperties());
     if (new File(loc).equals(new File(jarFile))) {
       XModelObject result = s.getChildByPath(entry);
       if (result == null && entry != null) {
         int q = entry.indexOf('/');
         int d = entry.indexOf('.');
         if (q > d && d >= 0) {
           String entry1 = entry.substring(0, q).replace('.', '/') + entry.substring(q);
           result = s.getChildByPath(entry1);
         }
       }
       if (result != null) return result;
     }
   }
   return (n == null) ? null : n.getModel().getByPath("/" + entry); // $NON-NLS-1$
 }