What is printed when the program is executed?

public class FirstIndex {
    public static int findFirstIndex(int[] arr, int index, int target) {
         if(index == arr.length) return -1;
         if(arr[index] == target) return index;
         return findFirstIndex(arr, index + 1, target);
    }
    public static void main(String[] args) {
         int[] arr = {5, 7, 9, 7, 3};
         System.out.println(findFirstIndex(arr, 0, 7));
    }
}