Servlet-Applet project. Architectural problem.

Hello, everybody!
I'm to make client-server web project, client works with different databases via server (using servlet). The protocol of the project is as follows:
- Client requests to �erver and gets applet.
- All communications between client and server are to be made via applet-servlet. So, client makes some operations using applet, then sends data to server. After the data being processed on the server side, client gets the possibilities to make further operations.
The problem is choosing the proper architecture. Having sigle applet and processing communications with single applet-servlet is not good, because I need to get client the possibility to choose database, then choose table, edit records and so on. I want to have applets for every type of operations. I mean, after client gets start applet, he sends the request to server, which processes it and gets another applet for database choosing and so on.
The question is: is it possible to build such architecture with many applets and data transfers between them?

Why does it need to be through applet?
Why can't the same applet take care of most (all?) your database chores?

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Sorry folks, just found my error. Forgot about the ObjectInputStream waiting on the Servlet side, so of course had a dead look...
Sorry!

Servlet/Applet communication, data limit?

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thanks for your replay,
I tried your suggestion but whatever I do it seems that tha applet only brings the first 5-10k of the image from the servlet. This is the value I get from instr.read() or any other type of read method. The value of bytes is not always the same.
Now I also have something new. For images greater than 100k or so I get this error:
java.io.IOException: Broken pipe
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     at java.lang.Thread.run(Compiled Code)
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bye

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hi,
I encountered a problem with tomcat 5.5. Grazing the whole web i didn't find any solution (some guys are having the same problem but they also got no useful hint up to now). The problem is as follows:
I try to build an applet-servlet communication using serialized objects. In my test scenario i write a serialized standard java object (e.g. a String object) onto the ObjectOutputStream of the applet/test-application (it doesn't matters wheter to use the first or the latter one for test cases) and the doPost method of the servlet reads the object from the ObjectInputStream. That works fine. But if i use customized objects (which should also work fine) the same code produces an classnotfound exception. When i try to read and cast the object:
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hi, thanks for the reply,
all my classes are in the web-inf/classes of the web-app and have an appropriate package structure. thus the TestMessage class is inside a package.
i tried some names for the testclass but it didn't matter. the exception stays the same. I also tried to put the jar in the common/lib but the problem stays.
Well the problem with loaded classes: As i mentioned in the post above i can instantiate an object of TestMessage in the code without any problems (so the classloader of my webapp should know the class!!)
only when reading from the objectinputstream the classloader doesn't seem to know the class?? maybe theres a parent classloader resposible for that and doesn't know the class?
strange behaviour...
p.s. sending the same object from the servlet to the client works well
regards
daniel
Message was edited by:
theazazel

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Servlet-Applet project. Architectural problem.

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