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Some intermediate but common questions  RSS feed

Mike Polin
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Consider an online auction app built with servlet and EJBs on j2ee1.3 beta with Cloudscape 3.6 under Win2K. Considered? Good. Here are the topichs with which I'm stucked.
1. Automatisation. Each auction has a duration. So I need smth. on the server to sleep (say for one day) and to perform some clearing tasks periodicaly and atomaticaly. What is the best practice of doing it? I've tried to use a Timer or Threads in my servlet, but I've not managed to make them work properly. I recive some weird exceptions only. What must I pay attention to? Some permissions or classpath settings? Maybe some have got a working piece of code? But please no FLUX or other commercial suggestions, I'm a student and cann't afford buying smth.
2. Session tracking. Under which circumstances will the server start a new session? If the request comes from a different IP or what? I've tried to simulate 2 concurent users from 2 browser windows on my machine, but the session ID was the same with all consequences. Ideas?
3. SSL. I've read a lot about it, but have found nearly nothing practical. In Sun's docs it is stated, that a developer must not wory about SSL implementation, because the servlets has it built-in. But what must I do at least exactly to make all or some of my comunications between browser and servlet or between servlet and EJB to go thru SSL? Where and what must I modify or set? Smth. in server start up files? Or somewhere else?
4. Object DB mapping. Each auction item has smth. like bid history. I have a DB Table for an auction. How can I put an info (a List, Collection or Hash of combo (bidderName, bidAmmount)) in one DB field? I've read a Cloudscape (an OR DB, so it must go "easily") docs, but there is all about preparedStatements, smth like "bidHistory" SERIALIZE (java.util.List). But I have all my EJBeans CMP, so I get all my default SQL generated from Deployment Tool and it gives me an Error "Can not find JDBC Class for class java.util.List". Must I place smth. in my classpath? rt.jar and all HOMES and so on are there. In Cloudscape docs there is a topic, that if one wants to SERIALIZE some java classes (native or user-defined), one must place 2 exact copies of class-files to client and to server. What could it mean? Where am I to put this classes exactly?
So this are my problems. Maybe I should start a new topic for each, but I'll see. Any help is highly appreciated. Thanks in advance.
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