Feature Request: customizable type names for states

[bannmann]

For an API entry point called Foo, Silverchain currently creates state interfaces called FooN and classes called FooNImpl (N = 0, 1, ...).

As discussed in chat, I believe that having numbers in a class name is unusual enough that it should help API users remember that these intermediate types are somewhat special, i.e. that keeping references to them in variables threatens the forward compatibility of their own code.

However, I now think that a fluent API could emphasize the fragility of its intermediate type names even more by incorporating non-latin Unicode characters. As Java identifiers can include any Unicode character that is a letter, digit or currency symbol in any language, one can certainly find a character that signals "this is unusual". For example, my current favorite is ⴵ because it is as large as a capital letter (and thus unlikely to be overlooked) and resembles an hourglass (fitting the "call in progress" nature of a method chain).

That said, Silverchain should not make that choice for API developers, but default to the safe, (hopefully) non-controversial FooN style. I propose adding an optional configuration setting called stateNameFormat which is a MessageFormat pattern:

stateNameTemplate	Interface Name	Class Name
{0}{1} (default setting)	Foo7	Foo7Impl
{0}ⴵ{1}	Fooⴵ7	Fooⴵ7Impl
{0}{1,number,0000}	Foo0007	Foo0007Impl
State{1}Of{0}	State7OfFoo	State7OfFooImpl

Silverchain would not have to validate anything here; if the resulting name is not a valid Java identifier or results in non-unique type names, the Java compiler will complain anyway:

stateNameTemplate	Interface Name	Class Name	Remark
Fun	Fun	FunImpl	Non-unique
{0}	Foo	FooImpl	Non-unique
{1}	7	7Impl	Invalid identifier: starts with a digit
{0}⛔{1}	Foo⛔7	Foo⛔7Impl	Invalid identifier: '⛔' is not a letter/digit/currency