자바 메인함수에서 args 질문드립니다.

public class Practice {
    public static void main(String[] args) throws Exception {
        // Check command line parameter usage
        if (args.length != 2) {
            System.out.println("Usage: java Practice John practice.txt");
            System.exit(1);
        }
 
        // Check if file exists
        File file = new File("practice.txt");
        if (!file.exists()) {
            System.out.println("File " + args[1] + " does not exist");
            System.exit(2);
        }
    }
}