> The provided java snippet is vanilla valid
Did not you still need the `java --source 11 ${filename_without_java_extension_because_JEP_330}` to use it? And you still need a wrapper class with a static method main in it.
Did not you still need the `java --source 11 ${filename_without_java_extension_because_JEP_330}` to use it? And you still need a wrapper class with a static method main in it.
One of the preview features he's using is JEP 445[1] that allows you to omit the wrapper class, as well as the arguments to main and the public and static modifiers.