This is achieved by sending the data back
and forth between the servers. Naturally, this consumes a lot of
resources. Therefore, storing a lot of data in the HttpSession could
considerably degrade the performance of your Web application even
when the request load is not very high.
2.18 J2EE Elements 97
In the deployment descriptor, web.xml, the distributable element indicates
that the Web application is programmed in such a way that servers that support clustering
can safely distribute the Web application across multiple servers. The distributable
element contains no subelements or data??”it is simply a flag (as
follows):
One of the prime features of a J2EE application is its scalability. The idea of scalability
is that the same code written to serve 100 users per day can serve tens of thousands
of users per second. Think of a music CD. The same music CD that you use in
your portable CD player with headphones can be inserted into a huge amplifying system
with many speakers and played for an entire stadium containing thousands of
people. All that??™s changed is the hardware you plugged the CD into. If there is a possibility
that your Web application will need to handle many more users in the future,
and you don??™t take the previously mentioned guidelines into account, the result
might be an expensive rewrite of your application.
2.18 J2EE Elements
This section describes the web.
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