Question

What is the difference between the following

import java.util.Scanner;
//Creating the scanner
Scanner input=new Scanner(System.in);
System.out.println("Enter the number 1");
int number1=input.nextInt();

vs

int number1=parseInt(args[0]);

Answer 1

The first one reads an integer from standard input. So you might run it as follows:

$ java Foo 
Enter the number 1               <<-- prompt from program.
42

The second one gets an integer from the command line. So you might run it as follows:

$ java Foo 42