Casting issues

Question about the task

Under discussion

Hi there, On this task all castings are giving an error so I cannot verity it. I mean: - new Double(xxxx) - new Float(xxx) the debugger says "Double(double)' is deprecated and marked for removal " and so for Float. This is my piece of code:

private static void initList(List<Number> list) {
        list.add(new Double(1000f));
        list.add(new Double("123e-445632"));
        list.add(new Float(-90 / -3));
        list.remove(new Double("123e-445632"));
    }

Any idea what's wrong?

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LuisRC

Level 39 , Gijón, Spain

13 February 2022, 07:19

Yes, I did. I though that until no having a green thick on errors you couldn't sent the taks for validation however I tried to see what happened and I got it validated. So the "deprecated" comments didn't count much.

LuisRC

Level 39 , Gijón, Spain

11 February 2022, 20:13

Ok and as always thanks for your help. There're some issues about the use of IntelliJ and about Java itself that still I don't understand.

Gellert Varga

Level 23 , Szekesfehervar, Hungary

12 February 2022, 21:01

Based on the comments below, the "deprecated" comment doesn't count for much, my understanding is that it's not much to bother with. Unfortunately I cannot help you on this subject. By the way, did you manage to solve the task?

Lisa

Level 41

11 February 2022, 14:16

Without code and requirements not much I can tell you. The deprecated warning shouldn't stop the code from compiling. And afaik CG uses Java 8 but the wrapper class constructors are deprecated from Java 9 on. So this shouldn't be a problem. I tried to set Java 8 feature level in my IntelliJ and see if the deprecation warning still pops up but unfortunately it does. So limiting featurs to 8 doesn't stop that warning to appear. You'd probably have to use Java 8 or add a proper @SuppressWarnings annotation, all for sure will do, @SuppressWarnings("all") (before the method or class definition). You also could make use of autoboxing or the valueOf method.

List<Number> list = new ArrayList<>();
list.add(1); // int, compiler automatically adds as Integer (autoboxing)
list.add(1.); // double, autoboxing to Double
list.add(Integer.valueOf(2)); // not necessary boxing to Integer
list.add(new Integer(3)); // deprecated since 9, CG uses 8 so this is legal code for 8. Evtl. use @SuppressWarnings
list.add(4F); // autoboxing to Float
list.forEach(n -> System.out.format("%s is Integer: %b%n", n, n instanceof Integer));

if (list.get(list.indexOf(4F)) instanceof Float)
    System.out.println("autoboxing to Float working");

Guadalupe Gagnon

Level 37 , Tampa, United States

11 February 2022, 21:50

Hey Lisa! You can set the module level to Java 8 to have it not show warnings for stuff now deprecated. Do so also in the Project Structure window but use the modules tab. Here is a screen shot:

You have to set the desired language level for all the modules.

Lisa

Level 41

11 February 2022, 22:16

Ha, yes, that's working. I fiddled with dependencies lately and that view was preset when I zapped over the modules tab. So I didn't see the language level dropdown but instead the JDK one. That way this makes sense. Already wondered why Jetbrains didn't take care of proper warnings 😜🤪 I thought Luis and I were much more intelligent than those guys over there, the bunglers, hahaha.