Array overrides array in ArrayList

Arrays are stored as references, so when you change the array one place, anywhere else you directly stored it will change to. Instead, make a brand new array with the same values, and store that. To do that, do array.clone(), so for you

ArrayList<int[]> lijstje = new ArrayList<int[]>();
public int[] data = {7,4,8,56,67,85,23,65,23,65,23,22};
int stemp;
int len = 10;
public void shellSort(){
    while (h <= len / 3) {
        h = h * 3 + 1;
    }
    while (h > 0) {

        for (outer = h; outer < len; outer++) {
            stemp = data[outer];
            inner = outer;

            while (inner > h - 1 && data[inner - h] >= stemp) {
                data[inner] = data[inner - h];
                inner -= h;
            }
            data[inner] = stemp;
            lijstje.add(data.clone()); // Notice here how it's data.clone() instead of just data
        }
        h = (h - 1) / 3;
    }
}

Here's an example showing how arrays are passed by referencing, this

int[] original = { 1, 2, 3 };
int[] passedByReference = original;
int[] cloned = original.clone();
System.out.println("Before:");
System.out.println(Arrays.toString(original));
System.out.println(Arrays.toString(passedByReference));
System.out.println(Arrays.toString(cloned));
original[0]=10;
System.out.println("After:");
System.out.println(Arrays.toString(original));
System.out.println(Arrays.toString(passedByReference));
System.out.println(Arrays.toString(cloned));

will have the following output

Before:
[1, 2, 3]
[1, 2, 3]
[1, 2, 3]
After:
[10, 2, 3]
[10, 2, 3]
[1, 2, 3]

as you can see, the cloned one is not affected, whereas the original and passed-by-reference ones are. In your code, you don't want changes to the original to affect the array you store, so you must clone it some way (array.clone() is a nice simple way for a 2D array).