java check if number has 4 digits code example

Example 1: len of number in java

Scanner s = new Scanner(System.in);
		int n = s.nextInt();
		
		int length = String.valueOf(n).length();
		System.out.print(length);

Example 2: how to get length of integer in java

int length = 0;
long temp = 1;
while (temp <= number) {
    length++;
    temp *= 10;
}
return length;