code: public void encodeChildren(FacesContext context, UIComponent component) throws IOException
      {
          if (context == null)
          {
              throw new NullPointerException("context");
          }
          if (component == null)
          {
              throw new NullPointerException("component");
          }
  
          if (component.getChildCount() > 0)
          {
              for (int i = 0, childCount = component.getChildCount(); i < childCount; i++)
              {
                  UIComponent child = component.getChildren().get(i);
                  if (!child.isRendered())
                  {
                      continue;
                  }
  
                  child.encodeAll(context);
              }
          }
      }
docs: Render all children if there are any.
  
  Note: this will only be called if getRendersChildren() returns true. A component which has a renderer with
  getRendersChildren() set to true will typically contain the rendering logic for its children in this method.
  
  @param context
  @param component
  @throws IOException