Presents your 
JAVA E-NEWSLETTER for September 16, 2002

<------------------------------------------->

DEPLOY RESOURCES WITH WAR FILES

You can use a Web Application Archive (WAR) file created from an Ant
build script to deploy Java code to a server. A Web application in Java has
a certain format located within a special directory named WEB-INF. This
directory contains a lib directory for jars, a classes directory for
unpackaged class files, and a web.xml file describing the application.

The rest of the Web application is just normal HTML, JSP, images, and
directories. These can be zipped up into a .war file and then deployed to a
server without having to make any modification to the server.

Most important, the server will notice when the .war file is placed in
the webapps/directory and automatically unpack it and add it to the server
without changes to the server.xml file. Deploying a change is a simple
matter of overwriting the .war file with a new one. The server will notice
again, unpack it, and reload all class files.

The Ant war task is an extension of the jar task with some special
handling for the WEB-INF directory, which may have four subtags: lib, classes,
webinf, and metainf. Files specified in these tags will go into their
particular directories, while metainf will go into the META-INF 
directory.

Here's an example of the war task:

<war warfile="ApplicationVersion2.war" webxml="xml/av2-web.xml">
  <fileset dir="html"/>
  <lib dir="lib/ext">
    <exclude name="oracle*.jar"/>
  </lib>
  <classes dir="build/servlets">
    <include name="**/*.class"/>
  </classes>
</war>

This example will build a file named ApplicationVersion2.war. It
gets its web.xml file from xml/av2-web.xml and includes every file in the
HTML directory. Additionally, it puts all the files in our lib/ext
directory into the war's WEB-INF/lib directory, except for the Oracle ones, and
puts all servlets sitting in the build/servlets directory into the
WEB-INF/classes directory.

----------------------------------------