William Ng is right; we need more details before we can understand why you think there is a problem.
What “ordered” means is that iterating the data structure causes its elements to be visited in a predictable order. You can create an
int[] or a
List (probably actually an
ArrayList) from an
IntStream object like this:-
Arrays and Lists (say List not ArrayList) are ordered; the order of visiting their elements is predictable and constant. If you don't change their contents or add more elements, both these loops will cause “1 2 69 4“ to be printed:-
Note: beware of using the get() method on a linked list; it can cause slow performance.
William Ng wrote:. . . . The elements have no ordering unless you order them yourself. And you do this by sorting. . . .
That is incorrect, I am afraid. Lists and arrays preserve insertion order or creation order. It is possible to alter their order by adding elements or sorting them; it is possible to alter the size of a List object but it is not possible to alter the length of an array object. People talk about ordered collections, sorted collections and unordered collections. In the case of a ordered collection, iteration produces the elements in the order they were added, allowing for the fact that such order can be altered, for example with
numbers.add(1, −999_999); It is possible to create ordered collections which iterate their contents backwards. A sorted data structure can be iterated in order of the value of its elements; if you sort
numbers in my example, that is changing their order. Some data structures, e.g.
this, are sorted automatically as elements are added. Some data structures are called unordered, which is an inaccurate term. If you iterate a
HashSet, you cannot easily predict what the order of elements will be, but you will usually get the same order.
Remembering that 0x41 is 65₁₀, see what difference you get if you omit 0x41 in line 99, even though you have a set with the same contents; the two versions would return
true from their equals() method. Also notice what happens if you run the loop repeatedly: you get the same output.