001/*
002 * This library is part of OpenCms -
003 * the Open Source Content Management System
004 *
005 * Copyright (c) Alkacon Software GmbH & Co. KG (http://www.alkacon.com)
006 *
007 * This library is free software; you can redistribute it and/or
008 * modify it under the terms of the GNU Lesser General Public
009 * License as published by the Free Software Foundation; either
010 * version 2.1 of the License, or (at your option) any later version.
011 *
012 * This library is distributed in the hope that it will be useful,
013 * but WITHOUT ANY WARRANTY; without even the implied warranty of
014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
015 * Lesser General Public License for more details.
016 *
017 * For further information about Alkacon Software, please see the
018 * company website: http://www.alkacon.com
019 *
020 * For further information about OpenCms, please see the
021 * project website: http://www.opencms.org
022 *
023 * You should have received a copy of the GNU Lesser General Public
024 * License along with this library; if not, write to the Free Software
025 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
026 */
027
028package org.opencms.ugc.client;
029
030import com.google.gwt.http.client.RequestBuilder;
031import com.google.gwt.http.client.RequestCallback;
032
033/**
034 * Helper class to execute an RPC call with a custom callback to enable/disable the wait animation.<p>
035 */
036public class CmsRpcCallHelper {
037
038    /** Counter to keep track of running requests. */
039    private CmsRequestCounter m_requestCounter;
040
041    /**
042     * Creates a new instance.<p>
043     *
044     * @param counter the request counter to keep track of running requests
045     */
046    public CmsRpcCallHelper(CmsRequestCounter counter) {
047
048        m_requestCounter = counter;
049
050    }
051
052    /**
053     * Executes the RPC call.<p>
054     *
055     * @param requestBuilder the request builder returned by the service interface
056     */
057    @SuppressWarnings("synthetic-access")
058    public void executeRpc(RequestBuilder requestBuilder) {
059
060        final RequestCallback callback = requestBuilder.getCallback();
061        RequestCallback callbackWrapper = new RequestCallback() {
062
063            public void onError(com.google.gwt.http.client.Request request, Throwable exception) {
064
065                m_requestCounter.decrement();
066                callback.onError(request, exception);
067            }
068
069            public void onResponseReceived(
070                com.google.gwt.http.client.Request request,
071                com.google.gwt.http.client.Response response) {
072
073                m_requestCounter.decrement();
074                callback.onResponseReceived(request, response);
075            }
076        };
077        requestBuilder.setCallback(callbackWrapper);
078        m_requestCounter.increment();
079        try {
080            requestBuilder.send();
081        } catch (Exception e) {
082            m_requestCounter.decrement();
083        }
084    }
085
086}