Main program
int number = 0;
System.out.println("The number of words in argv is " + argv.length);
if (argv.length == 0) {
number = 1234;
} else if (argv.length == 1) {
try {
number = Integer.parseInt(argv[0]);
} catch(NumberFormatException e) {
System.err.println("Number " + argv[0] + " invalid (" + e.getMessage() + ").");
System.exit(1);
}
} else {
System.err.println("usage: UseArgv number");
System.exit(1);
}
System.out.println("OK, number is " + number);
