Writing Custom Portlet Mode in WebSphere Portal

Steps
a.  Override generic portlet Dispatch method

private static final PortletMode CUSTOM_CONFIG_MODE = new PortletMode("config");

private static final PortletMode CUSTOM_EDIT_DEFAULTS_MODE = new PortletMode("edit_defaults");

protected void doDispatch(RenderRequest request, RenderResponse response) throws PortletException, IOException {

              if (!WindowState.MINIMIZED.equals(request.getWindowState())){

                     PortletMode mode = request.getPortletMode();                 

                     if (CUSTOM_CONFIG_MODE.equals(mode)) {

                           doCustomConfigure(request, response);

                           return;

                     }

                     else if (CUSTOM_EDIT_DEFAULTS_MODE.equals(mode)) {

                           doCustomEditDefaults(request, response);

                           return;

                     }

              }

              super.doDispatch(request, response);

       }

b. Add following in the portlet.xml

<custom-portlet-mode>

            <portlet-mode>config</portlet-mode>

      </custom-portlet-mode>

      <custom-portlet-mode>

            <portlet-mode>edit_defaults</portlet-mode>

</custom-portlet-mode>

Add following entries under the portlet tag

<supports>

      <portlet-mode>config</portlet-mode>

      <portlet-mode>edit_defaults</portlet-mode>

</supports>

Note: If a custom portlet mode defined in the deployment descriptor is not mapped to a custom portlet mode provided by WebSphere Portal, portlets must not be invoked in that portlet mode.  Ex: you can not create like "resize" mode for the portlet that deployed in websphere as websphere doesn't support it.