How to keep alive a session in Web Services?

Question

I have to do my project, that will be including some following features:
1. Login to Application through Web Services method. For example:
http://mydomain.com/web-services/Login?WSDL
2. After logging in, use mySms method to send message to Cellphone through Web Services! For example:
http://mydomain.com/web-services/mySms?WSDL
My questions are:
1. How can I keep alive the session after logging in the application in Web Services? In Web, I can use "Session".
2. If someone has not logged in the Application, he/she could not use mySms method for sending Sms. How can I do that?
3. I know, when I invoke a Web Services, one JavaBean has been called, and this bean is persistence with his own states. It means, if I set value to parameters of this bean, these values are persistence for invoked methods by other persons.
For example:
mySms bean has a private field "jid" inited with NULL value.
Person A invoked mySms.
Then, A set jid of mySms to value "A".
Person B invoked mySms. B got jid value. He receive the result value is "A".
The question is, how can I set mySms bean so that mySms bean is not persistence?
Thanks many!

Answer 1

Hi,
I can right away answer your FIRST Question.
Since WebServices are PURELY Based on SOAP which is in tern based on HTTP, they rely on a Stateless protocol.
I am sure you know that the HTTP is the STATELESS Protocol and so you can not maintain Session and so EACH Http REQUEST is considered as a SEPERATE REQUEST.
Now, still you want to maintain the Session in WebServices,
The simple answer is PASSING PARAMETERS.
Just Maintain your Session on Client (If you are using JSPs or Servlets to CAll WEBSERVICES then maintain Session through your HTTPSession) and each time you Invoke WebService PASS ON REQUIRED Parameters.
This Approach is Exactly like your URL REWriting OR your Parameters Passing through QUERY STRINGS.
I hope you got what I am saying!
Take care,
Himanshu/