Struts Session Question

[Picus Ameradeus]

I need to have session data be instantiated when a page loads - as opposed to on a form action - what is the best way to do this?

[Merrill Higginson]

Create a preparatory action that forwards to your JSP and call the action from the URL rather than th JSP. Example:

<action name="myForm" path="/preparePage1" type="com.mycompany.PreparePage1" >
  <forward name="success" path="/page1.jsp" />
</action>

URL:

http:myserver/myapp/preparePage1.do

This method allows you to put whatever you need in the Session prior to the JSP being displayed.

[Picus Ameradeus]

Ah ah makes perfect sense, what about if I wanted to ensure that no matter what page the person landed on, that class would be called?

[Merrill Higginson]

The above scenario only works for a single JSP. If you want code that executes before any JSP or action is executed, you should look at writing a Servlet Filter. This is only available if your Application server supports J2EE 1.4 or above (Tomcat 5). See chapter 11 of the Sun J2EE Tutorial

[Neerav Narielwala]

The session is normally maintained by session cookies. If you close your browser you lose the cookie. If you have disabled cookies on your machine then it also might not work.
In cases such as that you should be using the method response.encodeURL() to maintain the session for you in any hyperlinks you produce. Struts normally handles that for you though if necessary.

Hope this helps,
Bye.

[Ajay Xavier]

How about using a custom request processor to solve your purpose? Override the processPreprocess which performs session handling and that can be used for all the requests.

Regards,
Ajay.

[Merrill Higginson]

Ajay's solution would work well at performing logic before any action is executed. However, it would not work at performing logic before a JSP is dispalyed. If the user enters a URL such as http://myserver/myapp/mypage.jsp, the request processor is never invoked.