同一网站的多个域名之间访问共享信息

谁借莪１个温暖的怀抱￠ 2022-08-14 01:50 226阅读 0赞

1. ContextSingleListener

package test;

import javax.servlet.\*;  
import javax.servlet.http.\*;  
import java.io.\*;  
import java.util.\*;  
import org.apache.log4j.Logger;

public class ContextSingleListener extends HttpServlet implements ServletContextListener \{

Logger logger = Logger.getLogger(ContextSingleListener.class);

public void contextInitialized(ServletContextEvent sce) \{

ServletContext context=sce.getServletContext();

//初始化时往context里放东西  
    context.setAttribute("idlist",new Hashtable());  
    context.setAttribute("sessionid",new HashMap());

logger.info("初始化了Context,添加了idlist sessionid ");

public void contextDestroyed(ServletContextEvent sce) \{

//销毁时从context里移除东西  
    ServletContext context=sce.getServletContext();  
    context.removeAttribute("idlist");

\}  
\}

2.SessionSingleBean

package test;

import java.util.HashMap;  
import java.util.Hashtable;  
import javax.servlet.\*;  
import javax.servlet.http.\*;  
import javax.servlet.http.HttpServletRequest;  
import org.apache.log4j.Logger;

public class SessionSingleBean \{

Logger logger = Logger.getLogger(SessionSingleBean.class);

public SessionSingleBean() \{  
   \}

public HttpSession checkSession(HttpServletRequest request,String sid,HttpSession user)  
   \{  
     boolean issession=true;  
     HttpSession session = null;

Hashtable hashtable=(Hashtable)request.getSession().getServletContext().getAttribute("idlist");  
     HashMap hashMap=(HashMap)request.getSession().getServletContext().getAttribute("sessionid");  
     synchronized(this)  
     \{  
      Object obj = null;  
       try\{  
//      根据sessionId获取session  
        if(user==null)\{  
         obj=hashtable.get(sid);  
        \}else\{  
         obj=hashtable.get(user.getId());  
        \}   
         
        if(obj!=null)  
        \{  
          //这里使用Hashtable因为 Hashtable本身是synchronized 所以为了方便就使用Hashtable  
            
         session = (HttpSession)hashtable.get(user.getId());  
        \}else  
        \{  
            if(user!=null)\{  
             hashtable.put(user.getId(),user);  
           hashMap.put(request.getSession().getId(),user.getId());  
           logger.info(user.getId()+"  已经填入上下文");  
           logger.info(">>>>>>>>>>>>>>>>>>>>>>>>");  
           session = (HttpSession)hashtable.get(user.getId());   
            \}else\{  
              
           logger.info("根据所给的sessionid没有获取到session,且传入的user为空");  
           logger.info(">>>>>>>>>>>>>>>>>>>>>>>>");

\}  
       \}catch(Exception e)\{  
        e.printStackTrace();  
       \}  
     \}  
     return session;  
   \}  
 \}

3.SessionSingleListener

package test;

import javax.servlet.\*;  
import javax.servlet.http.\*;  
import java.io.\*;  
import java.util.\*;  
import org.apache.log4j.Logger;

public class SessionSingleListener extends HttpServlet implements HttpSessionListener \{

Logger logger = Logger.getLogger(SessionSingleListener.class);

public void sessionCreated(HttpSessionEvent se) \{

public void sessionDestroyed(HttpSessionEvent se) \{

//要销毁session  
     HttpSession session=se.getSession();  
     String id=session.getId();

ServletContext context=se.getSession().getServletContext();

Hashtable hashtable=(Hashtable)context.getAttribute("idlist");  
     HashMap hashMap=(HashMap)context.getAttribute("sessionid");

//如果没有相关信息

Object objname=hashMap.get(id);  
     if(objname==null) return;

String userid=objname.toString();

//获取session  
     HttpSession userext =(HttpSession)hashtable.remove(userid);  
     hashMap.remove(id);

logger.info("Session 过期 删除Context中的 用户"+userext.getAttribute("mobile\_no") +" 项");

\}  
 \}

一个网站有A,B两个域名，在A域名时调用SessionSingleBean往context中存入登录信息，跳到B域名时根据sessionid从context中取出相关登录信息。

当然也可以写加密类把相关信息加密，以get方式传送过去，然后解密。

4.web.xml

<listener>  
       <listener-class>test.ContextSingleListener</listener-class>  
  </listener>  
  <listener>  
       <listener-class>test.SessionSingleListener</listener-class>  
  </listener>

5.log4j.properties

\# An example log4j configuration file that outputs to System.out.  The  
\# output information consists of relative time, log level, thread  
\# name, logger name, nested diagnostic context and the message in that  
\# order.

\# For the general syntax of property based configuration files see the  
\# documenation of org.apache.log4j.PropertyConfigurator.

log4j.rootLogger=ERROR, A1

\# A1 is set to be a ConsoleAppender which outputs to System.out.  
log4j.appender.A1=org.apache.log4j.ConsoleAppender

\# A1 uses PatternLayout.  
log4j.appender.A1.layout=org.apache.log4j.PatternLayout

\# The conversion pattern uses format specifiers. You might want to  
\# change the pattern an watch the output format change.  
log4j.appender.A1.layout.ConversionPattern=%-4r %-5p \[%t\] %37c %3x - %m%n

\# In this example, we are not really interested in INNER loop or SWAP  
\# messages. See the effects of uncommenting and changing the levels of  
\# the following loggers.  
\# log4j.logger.org.apache.log4j.examples.SortAlgo.INNER=WARN  
\# log4j.logger.org.apache.log4j.examples.SortAlgo.SWAP=WARN