casting Arrays.asList causing exception: java.util.Arrays$ArrayList cannot be cast to java.util.ArrayList

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I'm new to Java and am trying to understand why the first code snippet doesn't cause this exception but the second one does. Since a string array is passed into Arrays.asList in both cases, shouldn't both snippets produce an exception or not produce an exception?

Exception in thread "main" java.lang.ClassCastException: java.util.Arrays$ArrayList cannot be cast to java.util.ArrayList

First snippet (causes no exception):

ArrayList<ArrayList<String>> stuff = new ArrayList<ArrayList<String>>();
String line = "a,b,cdef,g";
String delim = ",";
String[] pieces = line.split(delim);
stuff.add((ArrayList<String>) Arrays.asList(pieces));

Second snippet (causes above exception):

ArrayList<ArrayList<String>> stuff = new ArrayList<ArrayList<String>>();
String[] titles = {"ticker", "grade", "score"};
stuff.add((ArrayList<String>) Arrays.asList(titles));

If relevant, I'm using JavaSE 1.6 in Eclipse Helios.

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