Why do we use finally blocks?

Question

As far as I can tell, both of the following code snippets will serve the same purpose. Why have finally blocks at all?

Code A:

try { /* Some code */ }
catch { /* Exception handling code */ }
finally { /* Cleanup code */ }

Code B:

try { /* Some code */ }
catch { /* Exception handling code */ }
// Cleanup code

Answer 1

• What happens if an exception you're not handling gets thrown? (I hope you're not catching Throwable...)
• What happens if you return from inside the try block?
• What happens if the catch block throws an exception?

A finally block makes sure that however you exit that block (modulo a few ways of aborting the whole process explicitly), it will get executed. That's important for deterministic cleanup of resources.