Most elegant way to detect if a String is a number?

Question

Is there a better, more elegant (and/or possibly faster) way than

boolean isNumber = false;
try{
   Double.valueOf(myNumber);
   isNumber = true;
} catch (Nu         


        

Answer 1

If you want something that's blisteringly fast, and you have a very clear idea of what formats you want to accept, you can build a state machine DFA by hand. This is essentially how regexes work under the hood anyway, but you can avoid the regex compilation step this way, and it may well be faster than a generic regex compiler.