Yes. Exceptions shouldn't be used for flow control. In a real setting, you'd probably parse it as a long (and possibly catch that exception) then check the size for the actual type.

That being said, it is really easy to see what is happening, which is good.

And it looks pretty. :-)

Wouldn't the code be slower because of the try-catch check?

I like this idea too. the code is very clean

Impotent to notice here this solution isn't performance-wise.
It allocates in memory lots of intermediate arrays. That might be costly and has to be avoided.

Your solution is using a library?

Why people are voting "Best Practice" to a String concat loop?

ну ты гнида

It's possible to solve this problem in O(n*log(n)) time by reversing the keys and values of the second argument, and this is a O(n^2) solution.

It's my solution xD How dare you? Have a nice day

Such finesse! Being new to java myself, I didn't realize it had these tools to make this solution so succinct.