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Java Applet CACHE_VERSION Mac v/s Windows

Java Applets uses a property called as CACHE_VERSION which is of format that is comprised of 4 hexadecimal values separated by ".". The Applet plug-in uses this to determine whether to download new Jars or not. The sun documentation says that applet plugin would download the new jars if the CACHE_VERSION is higher than the previous one. My findings on this:

Windows plugin in IE/FF/Chrome/"Safari on windows" all will download new jars regardless of whether the jar cache version is greater or not. Earlier our version was 4.0.5.XXX, I tried updating version to 4.0.4.XXX or even 1.2.3.XXX and windows would happily download it.

We recently ran into an issue where applet would not work fro some mac users and it was random, the culprit was that during one deployment our operations team had updated jar as 4.0.6.XXX and we use XXX as svn changelist number of the jar file so we never changed the "4.0.5" portion. When the new build was deployed the jar version was again set to "4.0.5.XXX" in the jsp page.

The reason was the MAC Java plugin enforces the rules mentioned by Sun to download jars only if CACHE_VERSION is greater than the previous one. Changing the version to 5.2.1.XXX solved the issue and we changed the build also to reflect 5.2.1


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