Set session value in JSP and retrieve in java class using response.sendRedirect -

am trying value session fails. value in session set in jsp page same unable retrieve in java class. please resolve:

below code snippet :

interceptor entry in servlet-context.xml file :

<interceptor>     <mapping path="/**" />     <exclude-mapping path="/tabservice/pdfcreation/**"/>     <beans:bean class="com.mastek.ems.filter.executetimeinterceptor"></beans:bean> </interceptor> 

set session value in jsp page : index.jsp

//intiate session , set value  request.getsession(true).setattribute("user", "my_user");  system.out.println("inside jsp : ssn.getattrbute : " + request.getsession(false).getattribute("user"));  errorpage = false;   if(!errorpage){         string encstr = "encodevalue";     response.sendredirect("http://localhost/test/index.html#detailspage?en1="+encstr);  } else {        requestdispatcher dispatcher = getservletcontext().getrequestdispatcher("/error.jsp");     dispatcher.forward(request, response);   }  

try value in interceptor : executetimeinterceptor :

system.out.println("session object:"+request.getsession(false)); // prints null     system.out.println("session objectid1:"+request.getsession(false).getid()); // throws nullpointerexception      long starttime = system.currenttimemillis();     if(request.getsession(false) != null){         system.out.println("inside if : ssn data:"+request.getsession(false).getattribute("user"));         if( request.getsession(false).getattribute("user") != null ){          request.setattribute("starttime", starttime);             system.out.println("start time::with valid session:1:"+(new simpledateformat("dd/mm/yyyy:hh:mm:ss:ssss")).format(new date(system.currenttimemillis())));             return true;         }      } else{         system.out.println("start time::with invalid session::"+(new simpledateformat("dd/mm/yyyy:hh:mm:ss:ssss")).format(new date(system.currenttimemillis())));     }     request.setattribute("starttime", starttime);     utility.setresponseerror(response, "sessiontimedout");     return false; 

there chance of session getting lost when use redirect. if use redirect url, ensure 2 things.

the redirect url should same url used load current page.

also, use redirect code -

response.sendredirect(response.encoderedirecturl(your url)); 

check javadocs more info. https://tomcat.apache.org/tomcat-5.5-doc/servletapi/javax/servlet/http/httpservletresponse.html#encoderedirecturl(java.lang.string)

see similar issue here - session lost , created new in every servlet request