I took a deep breath and upgraded my MacBook to Mountain Lion yesterday.  Things are going pretty well, but a website I use regularly has a complicated security arrangement that uses several Java applets.  I noticed that the site had not shut down all its components.  A bit of investigation revealed that I needed a new version of Java (version 7 build 40).  This process created several Java fail events.

First, the download is 150 megabytes.  For a browser plugin that was supposed to solve problems.  Second, once downloaded, the install requires exiting Safari (and, presumably, any other browser).  Once installed (thankfully a fairly painless process), Java launches the default browser and asks if you want to check to be sure you have the most recent version of Java installed.

Pro-tip: before you do anything else, go to History / Reopen All Windows From Last Session.  Otherwise you may lose them.

Safari History Menu

When I clicked the button to check Java, I got the message “inactive plugin” with no additional explanation.  I checked Safari preferences.  Nope, Java was fully enabled.  Tried the Java version check again.  Same message.  Accidentally clicked the “inactive plugin” message and saw this:

Java Detection Using … Java

You read that correctly.  Checking the Java version requires … Java.  Wow.  I guess that’s one way of making sure Java is really there, but it’s kind of sketchy from where I’m sitting.