How to get the separate digits of an int number?

To do this, you will use the % (mod) operator.

int number; // = some intwhile (number > 0) {    print( number % 10);    number = number / 10;}

The mod operator will give you the remainder of doing int division on a number.

So,

10012 % 10 = 2

Because:

10012 / 10 = 1001, remainder 2

Note: As Paul noted, this will give you the numbers in reverse order. You will need to push them onto a stack and pop them off in reverse order.

Code to print the numbers in the correct order:

int number; // = and intLinkedList<Integer> stack = new LinkedList<Integer>();while (number > 0) {    stack.push( number % 10 );    number = number / 10;}while (!stack.isEmpty()) {    print(stack.pop());}

Convert it to String and use String#toCharArray() or String#split().

String number = String.valueOf(someInt);char[] digits1 = number.toCharArray();// or:String[] digits2 = number.split("(?<=.)");

In case you're already on Java 8 and you happen to want to do some aggregate operations on it afterwards, consider using String#chars() to get an IntStream out of it.

IntStream chars = number.chars();

How about this?

public static void printDigits(int num) {    if(num / 10 > 0) {        printDigits(num / 10);    }    System.out.printf("%d ", num % 10);}

or instead of printing to the console, we can collect it in an array of integers and then print the array:

public static void main(String[] args) {    Integer[] digits = getDigits(12345);    System.out.println(Arrays.toString(digits));}public static Integer[] getDigits(int num) {    List<Integer> digits = new ArrayList<Integer>();    collectDigits(num, digits);    return digits.toArray(new Integer[]{});}private static void collectDigits(int num, List<Integer> digits) {    if(num / 10 > 0) {        collectDigits(num / 10, digits);    }    digits.add(num % 10);}

If you would like to maintain the order of the digits from least significant (index[0]) to most significant (index[n]), the following updated getDigits() is what you need:

/** * split an integer into its individual digits * NOTE: digits order is maintained - i.e. Least significant digit is at index[0] * @param num positive integer * @return array of digits */public static Integer[] getDigits(int num) {    if (num < 0) { return new Integer[0]; }    List<Integer> digits = new ArrayList<Integer>();    collectDigits(num, digits);    Collections.reverse(digits);    return digits.toArray(new Integer[]{});}