Returning Index Of Last Occurrence Of A Number In Array

I'm making a program with several functions for an array of integers, one being to find the last occurrence of a given integer and returning it. The problem is that the method is returning -1 for every input, even though it's only supposed to do so for numbers not in the array. Here's the part of my code with the sections I'm having an issue with:

Driver

import java.util.Arrays;
public class ArrayMethodsDriver
{
public static void main(String[] args) {
int[] a = {7,8,8,3,4,9,8,7};
System.out.println("Last index of 8: " + ArrayMethods.findLast(a, 8));
System.out.println("Last index of 2: " + ArrayMethods.findLast(a, 2));

[Code] ....

As you can see, I'm testing 8(which should give a 6) and 2(which should give -1 because it's not in the array), and 4(which should give 4). The print statements all say -1.