public class Sample { private static Scanner sc = new Scanner(System.in); public static void main(String[] args) { String str; System.out.print("Enter: "); str = sc.nextLine(); int x = 0; if ((str == null) || (str.equals("") || (str.equals(" ")))) { System.out.println("Invalid"); } int sz = str.length(); for (int i = 0; i < sz; i++) { x = i; } if (Character.isDigit(str.charAt(x)) == false) { System.out.println("Its Not A Number."); } else if (Character.isDigit(str.charAt(x)) == true) { System.out.println("Its A Number."); } } }
this program is for checking if the input string or char is a number or not..
what i want is if the enterd value is " "(which is whitespace) and "" (which is empty) the program wont respond a StringOfIndexOutOfBounce... the compiler is pointing to this part
if (Character.isDigit(str.charAt(x)) == false) {
i dont know how to get out of this mess..
please correct my mistakes coz i've only done this program a while ago which was sir Json gave me , and i applied the simple logic ofthis in one of my programs.