HttpSessionStoreFilter.java

package cn.org.rapid_framework.web.session;

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.UUID;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.commons.lang.StringUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;
import org.springframework.web.filter.OncePerRequestFilter;

import cn.org.rapid_framework.web.session.store.JdbcSessionStore;
import cn.org.rapid_framework.web.session.store.SessionStore;
import cn.org.rapid_framework.web.session.wrapper.HttpServletRequestSessionWrapper;
import cn.org.rapid_framework.web.session.wrapper.HttpSessionSessionStoreWrapper;
import cn.org.rapid_framework.web.util.CookieUtils;

/**
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 * 
 * <h3>ʹ��:</h3>
 * ��filter���Զ�����spring������id=sessionStore�Ķ�����Ϊsession�洢
 * 
 * @See {@link SessionStore}
 * @See {@link MemcachedSessionStore}
 * @See {@link JdbcSessionStore}
 * @author badqiu
 *
 */
@SuppressWarnings("unchecked")
public class HttpSessionStoreFilter  extends OncePerRequestFilter implements Filter{
	private static Log log = LogFactory.getLog(HttpSessionStoreFilter.class);
	private String sessionIdCookieName = "_rapid_session_id";

	private String cookieDomain = null;

	SessionStore sessionStore;
	@Override
	protected void initFilterBean() throws ServletException {
		super.initFilterBean();
//		cookieDomain = FilterConfigUtils.getParameter(getFilterConfig(), "cookieDomain", cookieDomain);
//		cookiePath = FilterConfigUtils.getParameter(getFilterConfig(), "cookiePath", cookiePath);
//		sessionIdCookieName = FilterConfigUtils.getParameter(getFilterConfig(), "sessionIdCookieName", sessionIdCookieName);
		
		sessionStore = lookSessionStore();
//		wac.getAutowireCapableBeanFactory().autowireBeanProperties(this, AutowireCapableBeanFactory.AUTOWIRE_AUTODETECT, false);
	}

	protected SessionStore lookSessionStore() {
		WebApplicationContext wac = WebApplicationContextUtils.getRequiredWebApplicationContext(getServletContext());
		SessionStore store = (SessionStore)wac.getBean("sessionStore",SessionStore.class);
		if(logger.isInfoEnabled()) {
			logger.info("Using '"+store.getClass().getSimpleName()+"' SessionStore for HttpSessionStoreFilter");
		}
		return store;
	}
	
	public void setSessionIdCookieName(String sessionIdCookieName) {
		this.sessionIdCookieName = sessionIdCookieName;
	}

	public void setCookieDomain(String cookieDomain) {
		this.cookieDomain = cookieDomain;
	}
	
	public void setSessionStore(SessionStore sessionStore) {
		this.sessionStore = sessionStore;
	}

	@Override
	protected void doFilterInternal(HttpServletRequest request,HttpServletResponse response, FilterChain chain)throws ServletException, IOException {
		Cookie sessionIdCookie = getOrGenerateSessionId(request, response);
		String sessionId = sessionIdCookie.getValue();

		HttpSession rawSession = request.getSession();
		
		Map sessionData = loadSessionData(sessionId, rawSession);
		try {
			HttpSession sessionWrapper = new HttpSessionSessionStoreWrapper(rawSession,
					sessionStore,sessionId,sessionData);
			chain.doFilter(new HttpServletRequestSessionWrapper(request,sessionWrapper), response);
		}finally {
			try {
				sessionStore.saveSession(sessionId, sessionData,rawSession.getMaxInactiveInterval());
			}catch(Exception e) {
				log.warn("save session data error,cause:"+e,e);
			}
		}
	}

	private Map loadSessionData(String sessionId, HttpSession rawSession) {
		Map sessionData = null;
		try {
			sessionData = sessionStore.getSession(sessionId,rawSession.getMaxInactiveInterval());
		}catch(Exception e) {
			sessionData = new HashMap();
			log.warn("load session data error,cause:"+e,e);
		}
		return sessionData;
	}

	private Cookie getOrGenerateSessionId(HttpServletRequest request,
			HttpServletResponse response) {
		Map<String,Cookie> cookieMap = CookieUtils.toMap(request.getCookies());
		Cookie sessionIdCookie = cookieMap.get(sessionIdCookieName);
		if(sessionIdCookie == null || StringUtils.isEmpty(sessionIdCookie.getValue())) {
			sessionIdCookie = generateCookie(request,response);
		}else {
			sessionIdCookie.setMaxAge(request.getSession().getMaxInactiveInterval() * 60 * 60 * 1000);
		}
		return sessionIdCookie;
	}

	private Cookie generateCookie(HttpServletRequest request,HttpServletResponse response) {
		Cookie sessionIdCookie;
//		String sid = request.getSession().getId();
		String sid = null;
		if(StringUtils.isBlank(sid)) {
			sid = generateUUID();
		}
		sessionIdCookie = new Cookie(sessionIdCookieName,sid);
		if(cookieDomain != null)
			sessionIdCookie.setDomain(cookieDomain);
		sessionIdCookie.setPath(request.getContextPath());
		sessionIdCookie.setMaxAge(request.getSession().getMaxInactiveInterval());
		response.addCookie(sessionIdCookie);
		return sessionIdCookie;
	}

	private String generateUUID() {
		String uuid = UUID.randomUUID().toString();
		return org.springframework.util.StringUtils.replace(uuid, "-", "");
	}
}