Java program to convert a decimal number to binary number

import java.util.Scanner;

public class Main {

public static void main(String[] args) {
    int number; 

    Scanner in = new Scanner(System.in);

    System.out.println("Enter a positive integer");
    number = in.nextInt();

    if (number < 0) {
        System.out.println("Error: Not a positive integer");
    } else { 

        System.out.print("Convert to binary is:");
        //System.out.print(binaryform(number));
        printBinaryform(number);
    }
}

private static void printBinaryform(int number) {
    int remainder;

    if (number <= 1) {
        System.out.print(number);
        return; 
    }

    remainder = number %2; 
    printBinaryform(number >> 1);
    System.out.print(remainder);
}
}