cmssession.java

java 编写的程序

/*
* File   : $Source: /usr/local/cvs/opencms/src/com/opencms/core/CmsSession.java,v $
* Date   : $Date: 2002/01/08 10:42:07 $
* Version: $Revision: 1.19 $
*
* This library is part of OpenCms -
* the Open Source Content Mananagement System
*
* Copyright (C) 2001  The OpenCms Group
*
* This library 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 2.1 of the License, or (at your option) any later version.
*
* This library 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.
*
* For further information about OpenCms, please see the
* OpenCms Website: http://www.opencms.org
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

package com.opencms.core;

import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;

/**
 * This class implements a cms-session. This session should be used instead of
 * the HttpSession. In this session there will be implemented some mechanism for
 * session-failover in distributed-server environments.
 *
 * @author Michael Emmerich
 * @version $Revision: 1.19 $ $Date: 2002/01/08 10:42:07 $
 */
public class CmsSession implements I_CmsSession,I_CmsConstants {

    /**
     * The original HttpSession
     */
    private HttpSession m_session;

    /**
     * The sessiondata.
     */
    private Hashtable m_sessionData;

    /**
     * Constructs a new CmsSession based on a HttpSession.
     *
     * @param originalSession the original session to use.
     */
    public CmsSession(HttpSession originalSession) {
        m_session = originalSession;
        m_sessionData = (Hashtable)m_session.getAttribute(C_SESSION_DATA);

        // if there is no session-data, create a new one.
        if(m_sessionData == null) {
            m_sessionData = new Hashtable();
            m_session.setAttribute(C_SESSION_DATA, m_sessionData);
        }
    }

    /**
     * Gets a value from the session.
     *
     * @param name the key for the value.
     * @return the object associated with this key.
     */
    public Object getValue(String name) {
        return m_sessionData.get(name);
    }

    /**
     * Gets the names of all values stored in the session.
     *
     * @return String array containing all value names.
     */
    public String[] getValueNames() {
        String[] name = new String[m_sessionData.size()];
        Enumeration enu = m_sessionData.keys();
        for(int i = 0;i < m_sessionData.size();i++) {
            name[i] = (String)enu.nextElement();
        }
        return name;
    }

    /**
     * Puts a value into the session.
     *
     * @param name the key for the value.
     * @param value an object to be stored in the session.
     */
    public void putValue(String name, Object value) {
        m_sessionData.put(name, value);

        try {
            // indicate, that the session should be stored after the request.
            m_session.setAttribute(C_SESSION_IS_DIRTY, new Boolean(true));
        } catch (Exception exc) {
            if(I_CmsLogChannels.C_PREPROCESSOR_IS_LOGGING && A_OpenCms.isLogging()) {
                A_OpenCms.log(I_CmsLogChannels.C_OPENCMS_INFO, "[CmsSession] Error marking session as dirty " + exc.getClass().getName() + " " + exc.getMessage());
            }
        }
    }

    /**
     * Removes a value from the session.
     *
     * @param name the key for the value to be removed.
     */
    public void removeValue(String name) {
        m_sessionData.remove(name);

        // indicate, that the session should be stored after the request.
        m_session.setAttribute(C_SESSION_IS_DIRTY, new Boolean(true));
    }
}