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.http.services.Request;
020import org.apache.tapestry5.internal.services.RequestConstants;
021import org.apache.tapestry5.ioc.internal.util.InternalUtils;
022import org.apache.tapestry5.services.Ajax;
023import org.apache.tapestry5.services.ComponentEventRequestFilter;
024import org.apache.tapestry5.services.ComponentEventRequestHandler;
025import org.apache.tapestry5.services.ComponentEventRequestParameters;
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}