Moving items around in an ArrayList

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I came across this old question in my search for an answer, and I thought I would just post the solution I found in case someone else passes by here looking for the same.

For swapping 2 elements, Collections.swap is fine. But if we want to move more elements, there is a better solution that involves a creative use of Collections.sublist and Collections.rotate that I hadn’t thought of until I saw it described here:

http://docs.oracle.com/javase/6/docs/api/java/util/Collections.html#rotate%28java.util.List,%20int%29

Here’s a quote, but go there and read the whole thing for yourself too:

Note that this method can usefully be applied to sublists to move one
or more elements within a list while preserving the order of the
remaining elements. For example, the following idiom moves the element
at index j forward to position k (which must be greater than or equal
to j):

Collections.rotate(list.subList(j, k+1), -1);

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