What is JSESSIONID inward JSP-Servlet
JSESSIONID is a cookie generated past times Servlet containers similar Tomcat or Jetty as well as used for session administration inward J2EE spider web application for HTTP protocol. Since HTTP is a stateless protocol at that spot is no means for Web Server to relate ii dissever requests coming from the same customer as well as Session administration is the procedure to rails user session using unlike session administration techniques similar Cookies as well as URL Rewriting. If a Web server is using a cookie for session administration it creates as well as sends JSESSIONID cookie to the customer as well as and then the customer sends it dorsum to the server inward subsequent HTTP requests. JSESSIONID as well as session administration is a non exclusively a pop Servlet interview question but also appear inward diverse JSP interviews. Along amongst What is JSESSIONID interviewer are also interested inward when as well as how JSESSIONID is created inward Servlet as well as JSP which nosotros volition run into inward side past times side section.
When JSESSIONID created inward the Web application?
In Java J2EE application container is responsible for Session administration as well as past times default uses Cookie. When a user kickoff fourth dimension access your spider web application, session is created based on whether its accessing HTML, JSP or Servlet. if user asking is served past times Servlet than session is created past times calling request.getSession(true) method. it accepts a boolean parameter which instruct to practise session if its non already existed.
If yous telephone phone request.getSession(false) as well as then it volition either furnish null if no session is associated amongst this user or furnish the associated HttpSession object. If HttpRequest is for JSP page than Container automatically creates a novel Session amongst JSESSIONID if this characteristic is non disabled explicitly past times using page directive %@ page session="false" %>.
Once Session is created Container sends JSESSIONID cookie into response to the client. In illustration of HTML access, no user session is created. If client has disabled cookie than Container uses URL rewriting for managing session on which jsessionid is appended into URL every bit shown below:
If yous telephone phone request.getSession(false) as well as then it volition either furnish null if no session is associated amongst this user or furnish the associated HttpSession object. If HttpRequest is for JSP page than Container automatically creates a novel Session amongst JSESSIONID if this characteristic is non disabled explicitly past times using page directive %@ page session="false" %>.
Once Session is created Container sends JSESSIONID cookie into response to the client. In illustration of HTML access, no user session is created. If client has disabled cookie than Container uses URL rewriting for managing session on which jsessionid is appended into URL every bit shown below:
https://localhost:8443/supermart/login.htm;jsessionid=1A530637289A03B07199A44E8D531427
When HTTP session is invalidated(), to a greater extent than oft than non when the user logged off, onetime JSESSIONID destroyed as well as a novel JSESSIONID is created when the user farther login.
How to monitor HTTP asking to cheque JSESSIONID
You tin cheque the value of JSESSIONID coming inward every bit cookie past times monitoring HTTP request. If yous are running Tomcat Server inward NetBeans IDE inward your evolution environs as well as then yous tin piece of employment HTTP Server Monitor to cheque HTTP requests. You only require to enable it piece starting Tomcat Server shape Netbeans. After than amongst each asking yous tin run into all details of asking headers, session, cookies etc inward HTTP Server monitor screen. If yous hold back on JSESSIONID cookie it volition hold back like:
cookie JSESSIONID=1A530637289A03B07199A44E8D531427
You tin also enable HTTP asking as well as response inward Client side past times using tools similar ethereal or Wireshark. This tool tin monitor all HTTP traffic from as well as to your machine as well as past times looking at asking information yous tin run into JSESSIONID cookie as well as its value. That's all on What is JSESSIONID as well as How JSESSIONID is created within the J2EE application. We direct maintain seen that both Servlet as well as JSP tin endure responsible for Session creation but its done past times Container. yous tin squall back the value of SessionID which is represented past times JSESSIONID cookie when yous telephone phone request.getSession(). Session administration inward spider web applications is complex topic particularly when it comes to clustering as well as distributed session. On the other hand, JSESSIONID is i of those basics which every bit J2EE spider web application developer yous should endure aware of.
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