So I needed to copy an object that held an array of other complex objects that held still more complex objects along with a metric ton of ordinary data. And I was about to swear and write yet another copy constructor (because I am a recalcitrant C++ programmer apparently) when I suddenly realized that I was about to do way too much work.
If I implement the Cloneable interface and the clone() method on these objects, then I get a free bitwise copy of everything that they contain. So for that object with a metric ton of ordinary data, I just call super.clone() and I have now copied the metric ton of ordinary data and only need to fix up and clone the complex objects that I want to have new copies of, since my intent is to do a deep copy when calling clone().
So I ran around and implemented all of the necessary clone functions for half a dozen classes.
And the code base got 47 lines longer. Instead of a whole lot more lines of mechanical copying which would have pumped up the line count, but not actually done any more work.
OK. I guess I'm not yet too old to learn some new tricks. :)