How do I find out if first character of a string is a number?

Question

In Java is there a way to find out if first character of a string is a number?

One way is

string.startsWith(\"1\")

and do the abov

Answer 1

Regular expressions are very strong but expensive tool. It is valid to use them for checking if the first character is a digit but it is not so elegant :) I prefer this way:

public boolean isLeadingDigit(final String value){
    final char c = value.charAt(0);
    return (c >= '0' && c <= '9');
}