Testing for an integer in java

I was just wondering if there was a simple and easy way to test if a string(single char string) is a number.

Maybe some method I do not know about, or maybe something like

if (string[1].equals(\\#))

Any thoughts?

C:

main() {
char c = '9';
if(isdigit(c)) printf("%c is a number! \n", c);
}

Or even:

#define isnum(x) \
((x >= '0') && (x <= '9'))