An adding calculator in Java

Add.java

class Add {
  public static void main(String[] args) {
    if (args.length != 2) {
      System.err.println("Add can only add two numbers!");
      System.exit(1);
    }

    int a = 0;
    int b = 0;
    try {
      a = Integer.parseInt(args[0]);
      b = Integer.parseInt(args[1]);
    } catch (NumberFormatException e) {
      System.err.println("Add requires integer arguments");
      System.exit(2);
    }

    int c = a + b;
    System.out.println(Integer.toString(c));
  }
};