I don't agree with the criticism of Java's exception handling, since Java literally does make exactly the distinction between "1. A Bug in the system" as RuntimeException, and "2. A faulty situation that can't be avoided" as all other Exception, particularly IOException.

Although the same statement is used to catch both, you only catch both if you catch Exception. If you catch IOException or whatever other exceptions you need to catch and you opt to handle them, then RuntimeException will still propagate.

It is only a matter of understanding that this is the distinction, and writing the bodies of your catch blocks accordingly.

And if you are only writing a prototype, declare that it throws Exception, or if you can't, a catch (IOException ex) { throw new UncheckedIOException(ex); } really isn't that bad.