sessionfacade.java

一个论坛程序的简单实现

/*
 * Copyright (c) 2003, Rafael Steil
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, 
 * with or without modification, are permitted provided 
 * that the following conditions are met:
 * 
 * 1) Redistributions of source code must retain the above 
 * copyright notice, this list of conditions and the 
 * following  disclaimer.
 * 2)  Redistributions in binary form must reproduce the 
 * above copyright notice, this list of conditions and 
 * the following disclaimer in the documentation and/or 
 * other materials provided with the distribution.
 * 3) Neither the name of "Rafael Steil" nor 
 * the names of its contributors may be used to endorse 
 * or promote products derived from this software without 
 * specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT 
 * HOLDERS AND CONTRIBUTORS "AS IS" AND ANY 
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, 
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR 
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 
 * THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE 
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES 
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, 
 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER 
 * IN CONTRACT, STRICT LIABILITY, OR TORT 
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE
 * 
 * This file creation date: 12/03/2004 - 18:47:26
 * The JForum Project
 * http://www.jforum.net
 */
package net.jforum;

import java.util.ArrayList;
import java.util.List;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;

import net.jforum.entities.UserSession;
import net.jforum.util.preferences.ConfigKeys;
import net.jforum.util.preferences.SystemGlobals;

/**
 * @author Rafael Steil
 * @version $Id: SessionFacade.java,v 1.10 2004/11/06 18:03:48 rafaelsteil Exp $
 */
public class SessionFacade 
{
	private static final Map sessionMap = new LinkedHashMap();
	
	private SessionFacade() {}
	
	/**
	 * Add a new <code>UserSession</code> entry to the session
	 * 
	 * @param us The user session objetc to add
	 */
	public static void add(UserSession us)
	{
		add(us, JForum.getRequest().getSession().getId());
	}

	public static void add(UserSession us, String sessionId)
	{
		if (us.getSessionId() == null || us.getSessionId().equals("")) {
			us.setSessionId(sessionId);
		}
		
		sessionId = isUserInSession(us.getUsername());
		if (sessionId != null) {
			remove(sessionId);
		}

		sessionMap.put(us.getSessionId(), us);
	}
	
	/**
	 * Add a new entry to the user's session
	 * 
	 * @param name The attribute name
	 * @param value The attribute value
	 */
	public static void setAttribute(String name, Object value)
	{
		JForum.getRequest().getSession().setAttribute(name, value);
	}
	
	/**
	 * Gets an attribute value given its name
	 * 
	 * @param name The attribute name to retrieve the value
	 * @return The value as an Object, or null if no entry was found
	 */
	public static Object getAttribute(String name)
	{
		return JForum.getRequest().getSession().getAttribute(name);
	}

	/**
	 * Remove an entry fro the session map
	 * 
	 * @param sessionId The session id to remove
	 */
	public static void remove(String sessionId)
	{
		sessionMap.remove(sessionId); 
	}
	
	/**
	 * Get all registered sessions
	 * 
	 * @return <code>ArrayList</code> with the sessions. Each entry
	 * is an <code>UserSession</code> object.
	 */
	public static List getAllSessions()
	{
		return new ArrayList(sessionMap.values());
	}
	
	/**
	 * Gets the user's <code>UserSession</code> object
	 * 
	 * @return The <code>UserSession</code> associated to the user's session
	 */
	public static UserSession getUserSession()
	{
		return getUserSession(JForum.getRequest().getSession().getId());
	}
	
	public static UserSession getUserSession(String sessionId)
	{
		return (UserSession)sessionMap.get(sessionId);
	}

	/**
	 * Gets the number of session elements
	 * 
	 * @return The number of session elements currently registered
	 */
	public static int size()
	{
		return sessionMap.size();
	}
	
	/**
	 * Verify if the user in already loaded
	 * 
	 * @param username The username to check
	 * @return The session id if the user is already registered into the session, 
	 * or <code>null</code> if it is not.
	 */
	public static String isUserInSession(String username)
	{
		int aid = SystemGlobals.getIntValue(ConfigKeys.ANONYMOUS_USER_ID);
		
		for (Iterator iter = sessionMap.values().iterator(); iter.hasNext(); ) {
			UserSession us = (UserSession)iter.next();
			String thisUsername = us.getUsername();
			
			if (thisUsername == null) {
				continue;
			}
			
			if (us.getUserId() != aid && thisUsername.equals(username)) {
				return us.getSessionId();
			}
		}
		
		return null;
	}
	
	/**
	 * Verify if there is an user in the session with the 
	 * user id passed as parameter.
	 * 
	 * @param userId The user id to check for existance in the session
	 * @return The session id if the user is already registered into the session, 
	 * or <code>null</code> if it is not.
	 */
	public static String isUserInSession(int userId)
	{
		int aid = SystemGlobals.getIntValue(ConfigKeys.ANONYMOUS_USER_ID);
		
		for (Iterator iter = sessionMap.values().iterator(); iter.hasNext(); ) {
			UserSession us = (UserSession)iter.next();
			
			if (us.getUserId() != aid && us.getUserId() == userId) {
				return us.getSessionId();
			}
		}
		
		return null;
	}
	
	/**
	 * Verify is the user is logged in.
	 * 
	 * @return <code>true</code> if the user is logged, or <code>false</code> if is 
	 * an anonymous user.
	 */
	public static boolean isLogged()
	{
		return "1".equals(SessionFacade.getAttribute("logged"));
	}
}