Does the first array appear as a sequence within the second array?

Does the first array appear as a sequence within the second array? If so, return the first index where the first array can be found within the second. Otherwise, return -1. We will say that an empty array can be found in any array beginning at index 0.

findSubArray([5, 12], [2, 7, 5, 12, 14]) → 2

findSubArray([9], [4, 9, 7, 9]) → 1

findSubArray([4, 8], [4, 7, 8, 9, 10, 8, 4]) → -1

Could someone show me a java method to handle this question?

int findSubArray(int[] sub, int[] nums) {

}