A project that demonstrates some of the benefits of working with non-blocking reactive streams when I/O operations are slow.
The vaadin-frontend project hosts a simple Vaadin application, that can be run with mvn spring-boot:run in that module, or by running FrontendApplication in an IDE.
The spring-backend hosts the back end, and can be run with the same Maven command, or by running the BackendApplication in your IDE.
You can test the app at localhost:8080.
In the city view, there is a grid that lists names of cities. There are three buttons for fetching the cities in different ways (synchronously, asynchronously, reactive/non-blocking).
The backend call to fetch the cities takes around 3 seconds.
In the change password view, a user can change their password, as long as the new password is Vaadin123.
It uses a Context to make the name of the current user available to the client that initiates the backend call.