I haven't dealt with it but just a thought: if you put that same plist file in /Library/Preferences, does it supersede the user preference?

Thanks bpavlov-

com.oracle.javadeployment.plist doesn't start out being in /Library/Preferences by default so I'm not sure whether the Java 8 plugin is coded to check there for this key at all.

The general model that many applications follow, or are supposed to follow anyway, is to first look for global preferences in /Library/Preferences/ and if not found there, next check the user space at ~/Library/Preferences/ So its possible deploying the configured plist there could work.
I'm saying this, but I have zero insight into what that plist contains. so if it references items in the user's directory, it may not work at all. Its worth a shot though.

Personally, I think 8 u25 has two "updater" bugs.

1) If the software is up-to-date, it prompts to update.
2) If updates are disabled via the GUI, it successfully saves this setting at ~/Library/Preferences/com.oracle.javadeployment.plist. However, each time that Java preferences are opened, it deletes this plist file and starts anew.

I noticed that the version supplied on the Java website was 1.8.25 (or something, I've since removed it for other reasons), but the auto update downloads 1.8.26. There was actually a difference in versions.

Here's a possible workaround, though not well tested. Unknown if both referenced files are essential for this trick.

1. Via System Preferences' Java pane, uncheck "Check for Updates Automatically"
2. Click "Apply" and enter password if prompted.
3. Click "OK"
4. Locate ~/Library/Preferences/com.oracle.javadeployment.plist
5. Via "File" menu, choose "Get Info"
6. Check "Locked" and close window.
7. Locate ~/Library/Application Support/Oracle/Java/Deployment/deployment.properties
8. Via "File" menu, choose "Get Info"
9. Check "Locked" and close window.
10. Using Casper composer, create a package with these two files.
11. Deploy this to Mac clients, remembered to fill user template and fill existing user home directories.

I leave it for others to test the viability of this option. I do not know what long-term repercussions will occur as a result of deploying locked files.

Even after deploying this, the Java preferences GUI will incorrectly display a checkmark indicating that it auto-checks for updates.

Thanks for the advice and tips…

Anyone seeing whether there is a single key controlling this in Java 8 the way there was in Java 7?:

/Library/Preferences/com.oracle.java.Java-Updater JavaAutoUpdateEnabled -bool false