Question

Since there is no need to try/catch or specify un-checked exceptions, how are they are reported to the user?

Answer 1

how are they are reported to the user?
What is the best practice to handle
un-checked exceptions?

In our application, we barely use any exception at all: neither checked nor unchecked (we consider checked exceptions to be a Java idiosynchrasy unrelated to the problem domain we’re dealing with, so we wrap most checked exceptions inside cleaner APIs, using state testing methods).

The way we deal with it is simple: it’s a desktop application, if we catch an uncaught exception, we offer the user the possibility to send us a report. All the user has to do is click on “Report” and we get the full stack traces and other infos sent to one of our servers.

You can set up an application-wide uncaught exception handler like this:

Thread.setDefaultUncaughtExceptionHandler( new Thread.UncaughtExceptionHandler() {
    public void uncaughtException( final Thread t, final Throwable e ) {
       ...
       // Here we offer our user the possibility to 'report' the exception, YMMV
    }
 }

Typically there are zero exception happening in our software: we don’t use checked exception for flow control (unless when we’re using brain-dead APIs from the nineties, where this was common practice).

Some frameworks, like Spring, also have a pretty strong preference towards the “no checked exceptions” mentality.

So exceptions for us are really exceptionnal, hence the popup warning the user that the app crashed and offering them the possibility to send us the report.