max product of array -- ArrayIndexOutOfBoundsException

public class hello {

    private static int adjacentElementsProduct(int[] inputArray) {
        int sum = inputArray[0] * inputArray[1];
        for (int index = 1; index <= inputArray.length - 1; ++index) {
            final int product = inputArray[index] * inputArray[index + 1];
            if (product >= sum)
                sum = product;
        }
        return sum;
    }

    public static void main(String[] args) {
        int[] numo = {3, 6, -2, -5, 7, 3};
        int h = hello.adjacentElementsProduct(numo);
        System.out.println(h);
    }

}