Any way to make a generic List where I can add a type AND a subtype?
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Published on 2011-01-05T23:35:08Z
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2011/01/05
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I understand why I cannot do the following:
private class Parent {
};
private class Child extends Parent {
};
private class GrandChild extends Child {
};
public void wontCompile(List<? extends Parent> genericList, Child itemToAdd) {
genericList.add(itemToAdd);
}
My question is there ANY practical way to have a typesafe List where you can call add(E) where E is known to be only a Parent or a Child?
I vaguely remember some use of the "|" operator as used for wildcard bounds, but I cannot find it in the spec...
Thanks!
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