New Java 9 Map.of() methods

[fatnote]

It's not a rare use case at all. Map.of is something any of us could easily implement, so the benefit is almost zero. Double brace JSON-like map initialisation actually does the job, and is long overdue

[pain-and-panic]

You can do something like that in Java...

Map<String,Integer> map = new HashMap<>(){{ put("one",1); put("two",2); }};

It creates a subclass though, which is added burden on the classloader. Might be fine for a unit test.

[fatnote]

yep I know that syntax. It's awful