Windchill System Administrator's Guide

Downloading JAR Files
When a remote JAR file is available, but not cached locally, you are prompted to
download the file. Similarly, before a cached JAR file is reused, the remote
codebase is checked to see if a newer version of the file is available. If a newer
version is available, you are prompted for the action that you want to take. You
can download the file immediately, continue using the old file, or dynamically
download classes like a normal applet class loader would.
Note: The option to use an old file is enabled only if a previous JAR file exists
locally.
When downloading the new JAR file (which is normally compressed), you can
inflate the file. Inflating the JAR file after download makes the file bigger, but it
avoids the processing time that is required to inflate entries when they are loaded
later. Whether this CPU cost savings is worth the increased disk access to read
bigger entries, depends on the hardware. A user with a fast CPU but very slow
disk (laptop) might choose to leave the JAR file compressed.
If the specified JAR file is not available in the remote codebase, no local JAR file
is used, even if a previous one is available locally. The bootstrap loader
downloads classes like a regular applet class loader. To benefit from local JAR
files, the remote codebase must contain up-to-date JAR files reflecting its content.
The assumption is that, if a JAR file is no longer found, the codebase has
undergone some sort of change that would invalidate the previously cached JAR
file.
Administering Codebases
It is the responsibility of the Windchill administrator to create and recreate
codebase JAR files whenever any files in a codebase are changed.
The cached JAR files are standard JAR files. You can create them by using the Jar
utility included in the Java Developer's Kit (JDK), or by using other Zip utilities
as long as the resulting file names match those specified in bootstrap tags. They
should be created to contain all the Java class files and resource files from the
codebase that are required by the applet or application being bootstrapped. Any
files referenced that are not in the system class path or the specified JAR file are
not found.
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