struts2标签获取parameter,request,session,application中的值

paramters:
<s:property value="#parameters.propName"/>
or
<s:property value="#parameters['propName']"/>
	
request:
<s:property value="#request.propName"/>
or
<s:property value="#request['propName']"/>

session:
<s:property value="#session.propName"/>
or
<s:property value="#session['propName']"/>
 
application
<s:property value="#application.propName"/>
or
<s:property value="#application['propName']"/>