If I have a ArrayList which will hold items of type MyItem, then I declare it as:
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ArrayList<MyItem> items = new ArrayList<MyItem>();
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I then have a ArrayList which holds these items:
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ArrayList<ArrayList<MyItem>> allItems = new ArrayList<ArrayList<MyItem>>();
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I can then get an array of the items as:
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ArrayList[] itemList = allItems.toArray(new ArrayList[0]);
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Ok, now to get at each ArrayList<MyItem> I should be able to:
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ArrayList<MyItem> itemArray;
for ( int c = 0; c < itemList.length; c++ )
  itemArray = itemList[c];
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Except that the compiler complains about type safety in the last line. Fair enough, I have an generic ArrayList I am trying to put into an
ArrayList<MyItem>.

So how do I keep the compiler happy (other than add suppress warnings "unchecked" for the entire method)?

I tried:
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ArrayList<MyItem>[] itemList = allItems.toArray(new ArrayList<MyItem>[0]);
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 but that causes other errors.