Starting with 7u51, users are given an option to restore the security prompts for any prompts that were hidden more than 30 days prior to installing the latest Java release.
An option to hide a prompt in the future is included in some security prompts that are shown when an application starts (e.g., Do not show this again option in a security prompt). To insure the continued security of your system, it is recommended that you periodically restore the prompts that were hidden. Seeing the prompts again provides an opportunity to review the applications and ensure that you still want them to run.
To restore the prompts that were previously hidden, from the Java Control Panel Security tab, clickRestore Security Prompts. When asked to confirm the selection, click Restore All. The next time an application is started, the security prompt for that application is shown.
UPDATED: April 15, 2015