25 lines
1.5 KiB
Text
25 lines
1.5 KiB
Text
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JBoss is an implementation of the EJB 1.1 (and parts of 2.0) specification,
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that is, it is a server and container for Enterprise JavaBeans. In this it
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is similar to Sun's 'J2SDK Enterprise Edition' (J2EE), but the JBoss core
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server provides only an EJB server. The JBoss core does not include a web
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container for servlets/JSP pages, although there are bundles available that
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include either Tomcat or Jetty. The minimal core offering means that JBoss
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has minimal memory and disk space requirements. JBoss will run very
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effectively on a machine with 64 megabytes of RAM, and requires only a few
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megabytes of disk (including source code!). Sun's J2EE requires a minimum of
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128 megabytes of RAM, and 31 megabytes of disk space. Because of its small
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memory footprint, JBoss starts up about 10 times faster than J2EE. There is
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a built-in SQL database server for handling persistent beans, and this
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starts up automatically with the server (J2EE ships with the CloudScape SQL
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server, which has to be started separately).
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One of the nicest features of JBoss is its support for `hot' deployment. What
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this means is that deploying a Bean is a simple as copying its JAR file into
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the deployment directory. If this is done while the Bean is already loaded,
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JBoss automatically unloads it, then loads the new version. Contrast this
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with the rigmarole that other J2EE server makes us go through... JBoss is
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distributed under the LGPL, which means that it's free, even for commercial
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work, and the LGPL ensures that it remains that way.
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WWW: http://www.jboss.org/
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