Why can't an ArrayDeque be created for Chars?

Question

Java

Let's say I create an ArrayDeque for chars:

ArrayDeque<char> pass_raw = new ArrayDeque<char>();

Or I make a function that accepts it:

static public void stackUpper(ArrayDeque<char> pass) {
        if (pass.getLast() == 'A') {
            pass.addLast('B');
        } else {
            pass.addLast('A');
        }
    }

But it doesn't work! IntelliJ does not swear, but the compiler says that it expected a reference (to what?) instead of a char:

Main.java:5: error: unexpected type
    public static void stackUpper(ArrayDeque<char> pass) {
                                             ^
  required: reference
  found:    char

Main.java:39: error: unexpected type
        ArrayDeque<char> pass_raw = new ArrayDeque<char>();
                   ^
  required: reference
  found:    char
Main.java:39: error: unexpected type
        ArrayDeque<char> pass_raw = new ArrayDeque<char>();
                                                   ^
  required: reference
  found:    char

What am I doing wrong?

Answer 1

In java, generics cannot use primitives. There are wrapper classes for this. For char it's Character, for int it's Integer, etc.