Returns the RequestHandler/NotificationHandler/ResponseHandler corresponding to a specific LSP method.
Checks if a method has a handler registered for it. Used to determine if the server should send a request or a notification to the client (if the method has a handler, then the server will expect a response and thus send a request).
Registers a new handler of any kind (RequestHandler, NotificationHandler or ResponseHandler).
Registers a new dynamic ResponseHandler (used at runtime)
Checks if a function is correct handler function. These will only be registered at startup time and will never be unregistered.