Oracle hates its own product so much (Java) that it actively discourages people from ever running it. This is apparent in the JNLP dialogs you get when starting an application for the first time.
Both are really scary, with a big yellow alert, and a “I accept the risk…” checkbox.
The difference (since you probably didn’t find it) –
The first image is an “unrestricted access” dialog (which you should almost never run, no matter what the source) and the “so it is recommended not to run this application” probably understates the dangers.
The second image is a “limited access” dialog (which should be reasonably ok to run) and the “so it is recommended not to run this application” is completely overkill (unless, Oracle has errors in the sandbox code, which is something nobody can rule out, since, Oracle hates Java…)
So, Oracle hates Java so much that they pop up a dialog that looks 99% the same between two completely different cases. And, since you should not get into the habit of clicking that “I accept the risk” checkbox, even I have a difficult time recommending JNLP to anybody.
But hey, you should check out Lot Area Calculator, recently updated to have a JNLP link.