Streams

1. In Java 8+ you can make a stream of your int array. Call either Arrays.stream or IntStream.of.
2. Call IntStream#boxed to use boxing conversion from int primitive to Integer objects.
3. Collect into a list using Stream.collect( Collectors.toList() ). Or more simply in Java 16+, call Stream#toList().

Example:

int[] ints = {1,2,3};
List<Integer> list = Arrays.stream(ints).boxed().collect(Collectors.toList());

In Java 16 and later:

List<Integer> list = Arrays.stream(ints).boxed().toList();

The problem in

intList = new ArrayList<Integer>(Arrays.asList(intArray));

is that int[] is considered as a single Object instance since a primitive array extends from Object. This would work if you have Integer[] instead of int[] since now you're sending an array of Object.

Integer[] intArray = new Integer[] { 0, 1 };
//now you're sending a Object array
intList = new ArrayList<Integer>(Arrays.asList(intArray));

From your comment: if you want to still use an int[] (or another primitive type array) as main data, then you need to create an additional array with the wrapper class. For this example:

int[] intArray = new int[] { 0, 1 };
Integer[] integerArray = new Integer[intArray.length];
int i = 0;
for(int intValue : intArray) {
    integerArray[i++] = intValue;
}
intList = new ArrayList<Integer>(Arrays.asList(integerArray));

But since you're already using a for loop, I wouldn't mind using a temp wrapper class array, just add your items directly into the list:

int[] intArray = new int[] { 0, 1 };
intList = new ArrayList<Integer>();
for(int intValue : intArray) {
    intList.add(intValue);
}

First of all, for initializing a container you cannot use a primitive type (i.e. int; you can use int[] but as you want just an array of integers, I see no use in that). Instead, you should use Integer, as follows:

ArrayList<Integer> arl = new ArrayList<Integer>();

For adding elements, just use the add function:

arl.add(1);  
arl.add(22);
arl.add(-2);

Last, but not least, for printing the ArrayList you may use the build-in functionality of toString():

System.out.println("Arraylist contains: " + arl.toString());  

If you want to access the i element, where i is an index from 0 to the length of the array-1, you can do a :

int i = 0; // Index 0 is of the first element
System.out.println("The first element is: " + arl.get(i));

I suggest reading first on Java Containers, before starting to work with them.

You can use the following instruction:

new ArrayList<>(Arrays.asList(array));