    001// Copyright 2010 The Apache Software Foundation
    002//
    003// Licensed under the Apache License, Version 2.0 (the "License");
    004// you may not use this file except in compliance with the License.
    005// You may obtain a copy of the License at
    006//
    007// http://www.apache.org/licenses/LICENSE-2.0
    008//
    009// Unless required by applicable law or agreed to in writing, software
    010// distributed under the License is distributed on an "AS IS" BASIS,
    011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    012// See the License for the specific language governing permissions and
    013// limitations under the License.
    014
    015package org.apache.tapestry5.internal.services.ajax;
    016
    017import java.io.IOException;
    018
    019import org.apache.tapestry5.internal.services.RequestConstants;
    020import org.apache.tapestry5.ioc.internal.util.InternalUtils;
    021import org.apache.tapestry5.services.Ajax;
    022import org.apache.tapestry5.services.ComponentEventRequestFilter;
    023import org.apache.tapestry5.services.ComponentEventRequestHandler;
    024import org.apache.tapestry5.services.ComponentEventRequestParameters;
    025import org.apache.tapestry5.services.Request;
    026
    027/**
    028 * Filter for the {@link Ajax} {@link ComponentEventRequestHandler} that informs the {@link AjaxFormUpdateController}
    029 * about the form's client id and component id. Partial renders work with the
    030 * AjaxFormUpdateController to ensure that the Form data, if any, is collected and rendered
    031 * as part of the response.
    032 *
    033 * @since 5.2.0
    034 */
    035public class AjaxFormUpdateFilter implements ComponentEventRequestFilter
    036{
    037    private final Request request;
    038
    039    private final AjaxFormUpdateController ajaxFormUpdateController;
    040
    041    public AjaxFormUpdateFilter(Request request, AjaxFormUpdateController ajaxFormUpdateController)
    042    {
    043        this.request = request;
    044        this.ajaxFormUpdateController = ajaxFormUpdateController;
    045    }
    046
    047    public void handle(ComponentEventRequestParameters parameters, ComponentEventRequestHandler handler)
    048            throws IOException
    049    {
    050        String formClientId = request.getParameter(RequestConstants.FORM_CLIENTID_PARAMETER);
    051        String formComponentId = request.getParameter(RequestConstants.FORM_COMPONENTID_PARAMETER);
    052
    053        if (InternalUtils.isNonBlank(formClientId) && InternalUtils.isNonBlank(formComponentId))
    054            ajaxFormUpdateController.initializeForForm(formComponentId, formClientId);
    055
    056        handler.handle(parameters);
    057    }
    058}