Why does A == A evaluates to false?

I'm working on a Java program that takes an input int[] called items which looks like

[A,A,A,A,B,C,C,D,A,A,E,E,E,E]

And my output, A String[] called Letters that should look like

[A,B,C,D,A,E]

And another Array, an int[] called count that should look like

[4,1,2,1,2,4]

And I have code that looks like below, but for some reason, every time I run it it won't work. The print statements read that it doesn't ever go to the if statement. Line 2 on the second loop reads:

Check if A == A

Then it goes to the else statement and prints

A != A

What am I doing wrong? Why is A (items[0]) not equal to A (checkagainst)?

for (int x = 0; x < items.length; x++){
        System.out.println("\n\nCheck if "+checkagainst+" == "+items[x]);//line 2
        if (checkagainst == items[x]){
            count[position] += 1;
            System.out.println("Iteration:" + x
                    +"\n Letters: "+Arrays.toString(letters)
                    +"\n Count: "+Arrays.toString(count)
                    +"\nSwitch: if");
        }
        else{
            System.out.println("checkagainst != items[x]");
            letters[position] = items[x];
            count[position] = 1;
            checkagainst = items[x];
            position ++;
            System.out.println("Iteration:" + x
                                +"\n Letters: "+Arrays.toString(letters)
                                +"\n Count Arrays"+Arrays.toString(count)
                                +"\ncheckagainst: "+ checkagainst
                                +"\nSwitch: else");
        }
    }