/**
  * Dump the component tree to log.
  *
  * @param filter Show only the components, which path contains the filterstring.
  */
 public void debugComponentTrees(String filter) {
   log.info("debugging ----------------------------------------------");
   for (ComponentData element : WicketTesterHelper.getComponentData(getLastRenderedPage())) {
     if (element.path.matches(".*" + filter + ".*")) {
       log.info("path\t" + element.path + " \t" + element.type + " \t[" + element.value + "]");
     }
   }
 }