SF/JavaOne, Day 3, JavaGenericsWhaaaa?!

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I'm at the Java Collections talk and they're bringing up the issue of
type safety with generics in java 1.5.  The speaker just told me
somethign that sent a shiver up my spine.  Let's say you compiled
the following code in java1.4:

class Old {

    static void addIntegerToList(List list) {

        list.Add(new Integer(42));

    }

}

then in java1.5 you write and compile the following code:

class New {

    static void Foo() {

        List<String> strings = new ArrayList<String>();

        Old.addIntegerToList(strings);

        Srting firstString = strings.getAt(0);

    }

}

Then the above code compiles fine without a single warning!  Ack!

Double-ack!

Ack*Ack*Ack!

The compiler will make you think that everything is typesafe and you
won't know that anything is wrong with your type system until it blows
up at runtime.