Question

Write an interactive Java class which accepts an input argument when the application is executed from the command-line. Accept input from the user and compare the value entered to the command-line argument value. If the strings do not equal, display "INVALID VALUE! TRY AGAIN!", otherwise display "PERMISSION GRANTED!" and exit the program.

Answer 1

import java.util.Scanner;

public class MatchCommandLineArgument {

    public static void main(String[] args) {
        if (args.length == 0) {
            System.out.println("Please provide a string as command line argument");
        } else {
            Scanner in = new Scanner(System.in);
            String s;
            while (true) {
                System.out.print("Enter a string: ");
                s = in.nextLine();
                if (s.equals(args[0])) {
                    System.out.println("PERMISSION GRANTED!");
                    break;
                } else {
                    System.out.println("INVALID VALUE! TRY AGAIN!");
                }
            }
            in.close();
        }
    }
}