Differences between these two scanner codes?

{        static void first

String line = "";

for (int i = 0; i < 2; i++) {

Scanner scanner = new Scanner (System.in);

System.out.println("write something:");

if (scanner.hasNextInt()) {

line = scanner.nextLine();

}

System.out.println("it's a: " + line);

}

static void second (){

double nr = 0;

while (nr < 2) {

Scanner scanner = new Scanner (System.in);

System.out.println("write again:");

nr = scanner.nextDouble();

}

System.out.println("it's a:" + nr);

}

}

}