1. 新建两个应用：
test1
|------WEB-INF
| |------web.xml
|------test.jsp
test.jsp代码
<% session.setAttribute("test1Session","test1Session"); session.getServletContext().setAttribute("t1_session",session); out.println("Application /test1 is ok!<br>"); if(session.getServletContext().getContext("/test2")!=null){ HttpSession t2_session = (HttpSession)session.getServletContext().getContext("/test2").getAttribute("t2_session"); if(t2_session!=null){ String str = (String)t2_session.getAttribute("test2Session"); String path = request.getContextPath(); out.println("Application "+path +":"+str+"<br>"); }else{ out.println("Application /test2 no data!"); } } %>test2
|------WEB-INF
| |------web.xml
|------test.jsp
test.jsp代码
<% session.setAttribute("test2Session","test2Session"); session.getServletContext().setAttribute("t2_session",session); out.println("Application /test2 is ok!<br>"); if(session.getServletContext().getContext("/test1")!=null){ HttpSession t1_session = (HttpSession)session.getServletContext().getContext("/test1").getAttribute("t1_session"); if(t1_session!=null){ String str = (String)t1_session.getAttribute("test1Session"); String path = request.getContextPath(); out.println("Application "+path +":"+str+"<br>"); }else{ out.println("Application /test1 no data!"); } } %>2. 配置tomcat，设置crossContext = true，让两个应用可以在tomcat中交叉使用上下文环境。
<Context path="/test1" docBase="C:/test1" reloadable="true" crossContext="true"></Context>
<Context path="/test2" docBase="C:/test2" reloadable="true" crossContext="true"></Context>
3. 启动Tomcat，访问:8080/test1/test.jsp
页面输出：Application /test1 is ok!------------------------test1存储session成功
Application /test2 no data!--------------------test2还没有被访问，所以test2的session中没有数据
访问:8080/test2/test.jsp
页面输出：Application /test2 is ok!------------------------test2存储session成功
Application /test2:test1Session-------------test1Session来自test1应用中session
刷新:8080/test1/test.jsp
页面输出：Application /test1 is ok!------------------------test1存储session成功
Application /test1:test2Session-------------test2Session来自test2应用中session