com.manydesigns.elements.messages.SessionMessages.java Source code

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Here is the source code for com.manydesigns.elements.messages.SessionMessages.java

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/*
 * Copyright (C) 2005-2013 ManyDesigns srl.  All rights reserved.
 * http://www.manydesigns.com/
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 3 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */

package com.manydesigns.elements.messages;

import com.manydesigns.elements.ElementsThreadLocals;
import com.manydesigns.elements.xml.XhtmlBuffer;
import com.manydesigns.elements.xml.XhtmlFragment;
import org.apache.commons.lang.StringEscapeUtils;
import org.jetbrains.annotations.NotNull;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.LinkedBlockingQueue;

/**
 * @author Paolo Predonzani     - paolo.predonzani@manydesigns.com
 * @author Angelo Lupo          - angelo.lupo@manydesigns.com
 * @author Giampiero Granatella - giampiero.granatella@manydesigns.com
 * @author Alessio Stalla       - alessio.stalla@manydesigns.com
 */
public class SessionMessages {
    public static final String copyright = "Copyright (c) 2005-2013, ManyDesigns srl";
    public static final String INFO_MESSAGES_KEY = "info_messages_key";
    public static final String WARNING_MESSAGES_KEY = "warning_messages_key";
    public static final String ERROR_MESSAGES_KEY = "error_messages_key";

    public final static Logger logger = LoggerFactory.getLogger(SessionMessages.class);

    public static void addInfoMessage(String msg) {
        getInfoQueue().add(StringEscapeUtils.escapeXml(msg));
    }

    public static void addInfoMessage(XhtmlFragment xml) {
        XhtmlBuffer buf = new XhtmlBuffer();
        xml.toXhtml(buf);
        getInfoQueue().add(buf.toString());
    }

    public static void addWarningMessage(String msg) {
        getWarningQueue().add(StringEscapeUtils.escapeXml(msg));
    }

    public static void addWarningMessage(XhtmlFragment xml) {
        XhtmlBuffer buf = new XhtmlBuffer();
        xml.toXhtml(buf);
        getWarningQueue().add(buf.toString());
    }

    public static void addErrorMessage(String msg) {
        getErrorQueue().add(StringEscapeUtils.escapeXml(msg));
    }

    public static void addErrorMessage(XhtmlFragment xml) {
        XhtmlBuffer buf = new XhtmlBuffer();
        xml.toXhtml(buf);
        getErrorQueue().add(buf.toString());
    }

    public static List<String> consumeInfoMessages() {
        List<String> result = new ArrayList<String>();
        getInfoQueue().drainTo(result);
        return result;
    }

    public static List<String> consumeWarningMessages() {
        List<String> result = new ArrayList<String>();
        getWarningQueue().drainTo(result);
        return result;
    }

    public static List<String> consumeErrorMessages() {
        List<String> result = new ArrayList<String>();
        getErrorQueue().drainTo(result);
        return result;
    }

    public static BlockingQueue<String> getInfoQueue() {
        return getQueue(INFO_MESSAGES_KEY);
    }

    public static BlockingQueue<String> getWarningQueue() {
        return getQueue(WARNING_MESSAGES_KEY);
    }

    public static BlockingQueue<String> getErrorQueue() {
        return getQueue(ERROR_MESSAGES_KEY);
    }

    protected static BlockingQueue<String> getQueue(String queueName) {
        HttpServletRequest req = ElementsThreadLocals.getHttpServletRequest();
        if (req == null) {
            logger.debug("No request available. Returning dummy queue.");
            return new LinkedBlockingQueue<String>();
        }
        HttpSession session = req.getSession();
        BlockingQueue<String> infoQueue;
        synchronized (session) {
            infoQueue = (BlockingQueue) session.getAttribute(queueName);
            if (infoQueue == null) {
                // install a new queue
                infoQueue = new LinkedBlockingQueue<String>();
                session.setAttribute(queueName, infoQueue);
            }
        }
        return infoQueue;
    }

}