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Java - How to make an arraylist of arraylists

I had to make an arraylist of arraylists.  The reason that I was doing this, was that I had to eliminate duplicates from a resultset.  The easiest way to do this was to put the resultset into an arraylist so that I could operate on it, because you can't iterate or use a resultset twice in Java.

Here are a few examples of the constructors to make an arraylist of arraylists:

   ArrayList<ArrayList<Object>> allData = new ArrayList<ArrayList<Object>>();

 ArrayList<ArrayList<String>> allString = new ArrayList<ArrayList<String>>();

 ArrayList<ArrayList<int>> allInts = new ArrayList<ArrayList<int>>();

Easy once you know how.

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