Question

Well, I’m trying to figure out this thing. How would you code something like this (in Javglish):

if(input != a number)
{
    do something
}

How would I code this?

Answer 1

From http://rosettacode.org/wiki/Determine_if_a_string_is_numeric#Java:

(Poorly optimized, better examples inside the link, like the RegEx one)

public boolean isNumeric(String input) {
  try {
    Integer.parseInt(input);
    return true;
  }
  catch (NumberFormatException e) {
    // s is not numeric
    return false;
  }

Edit for future viewers: The aforementioned RegEx method is much more elegant, but is a little harder to follow, if you aren’t familiar with Regular Expressions:

public static boolean isNumeric(String inputData) {
  return inputData.matches("[-+]?\\d+(\\.\\d+)?");
}