Block use of `Optional#get`

[AB-xdev]

There are nearly always better alternative for Optional#get:

• Use mapping .map() directly
• Use .orElseThrow, .orElse or .or

The .get() method usually indicates that a check (e.g. isPresent()) was used before extracting the value.

[AB-xdev]

Note:

Java 8 was a huge improvement to the platform, but one of the few mistakes we made was the naming of Optional.get(), because the name just invites people to call it without calling isPresent(), undermining the whole point of using Optional in the first place. (If this was the worst mistake we made in such a big release, then we did pretty well.)

During the Java 9 time frame, we proposed to deprecate Optional.get(), but the public response to that was ... let's say cold. As a smaller step, we introduced orElseThrow() in 10 (see https://bugs.openjdk.java.net/browse/JDK-8140281) as a more transparently named synonym for the current pernicious behavior of get(). IDEs warn on unconditional use of get(), but not on orElseThrow(), which is a step forward in teaching people to code better. The question is, in a sense, a "glass half empty" view of the current situation; get() is still problematic.

We'd love to improve the situation further in future version, but it will probably take some time to bring more of the community around.
- Brian Goetz

https://stackoverflow.com/a/49159955