Return first digit of an integer

Question

How in Java do you return the first digit of an integer.?

i.e.

345

Returns an int of 3.

Answer 1

To separate digits of an integer from left to right I use 2 different methods, the first one to count how many digits the integer is made up of and then I split them from left to right by dividing the integer by 10 raised to the power of the number of digits minus 1.

//method to separate digits of an integer from left to right
private static void separateDigits(int num){
    int numOfDigits = countNumberOfDigits(num);
    for (int numOfZeros = numOfDigits-1; numOfZeros >= 0 ; --numOfZeros){
        int divisor = (int) Math.pow(10, numOfZeros);
        System.out.print( Math.abs(num) / divisor + " // " );
        num %= divisor;
    }
}

//method to count number of digits
private static int countNumberOfDigits(int num){
    int numOfDigits=0;
    //using absolute value of num allows method to work even with negative integers
    while(Math.abs(num) > 0){ 
        num = num / 10;
        numOfDigits++; //this counts the number of times the "while" loops
    }
    return numOfDigits;
}

No use of Arrays or recursive methods just simple division with "/" and "%".

Invoking the method:

public static void main(String args[]) {

separateDigits( -123456789 );

}

yields: 1 // 2 // 3 // 4 // 5 // 6 // 7 // 8 // 9 //