Type Parameter Issues

[high lodge]

This one has a lot of code. (it was too much for discord, find em here https://pastebin.com/uXUCwmVQ)
The issue is in the construction of a request. I have no clue what is going on, but for some reason, I can do this with absolutely no errors:

System.out.println(Request.of(RType.INTEGER, new ArrayList<>(), 3, true));

And, yes, I tried this:

System.out.println(new Request<>(RType.INTEGER, new ID(""), true));

For some reason, I can set an integer to a boolean? I think I am a very advanced programmer, but this has me stumped. Any help appreciated!

[dull sluice]

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[manic kestrel]

Well booleans are just intergers under the hood (0 being false and 1 being true).

Though not fully sure how requests work as I've never used them

Ah I see it's the pastebin you posted

Let me take a quick look

Okay so the first one works as it is using this function:

public static <H> Request<H> of(IRType<H> type, List<ID> activeIds, int idLength, H data) {```

What's confusing regarding it?

[high lodge]

Wdym

Well Boolean doesn't extend integer, so I have no clue why it's allowing me to do that

And same with other stuff like strings

[manic kestrel]

That's just how primitive types work

https://en.wikipedia.org/wiki/Boolean_data_type

[high lodge]

Well that's not how it's worked for me in the past

And I'm doing Boolean no boolean I'm pretty sure

[manic kestrel]

If you are using the keywords true and false it will be using boolean

[high lodge]

Ok

But there is no string, only String, so I have no clue on that one

[manic kestrel]

System.out.println(Request.of(RType.STRING, new ArrayList<>(), 3, "string"));

Does this work?

[manic kestrel]

And string is technically not a primitive type

As a string under the hood is actually a char[]

[next sparrow]

RType implements IRType<Object>, therefore although elements in your enum use different generics, they all in fact use Object generic.
That's why your function with different types runs just fine, because your Integer and Boolean treated as Object, so no error here!

[manic kestrel]

The primitives only matter in the boolean -> int conversion, they have nothing to do with strings

[next sparrow]

I guess you could've avoided that, if you defined each RType value individually in a separated classes, implementing IRType<Integer>, IRType<Boolean> and such instead of blank IRType<Object>

But i dunno, I fall asleep

[next sparrow]

you see what I mean? @high lodge

Request.of(RType.INTEGER, new ArrayList<>(), 3, true)

is the same as:

Request.of<Object>(RType.INTEGER, new ArrayList<>(), 3, true)

[high lodge]

Yeah. If I add a variable like
Request<Integer>
it recognizes it as an error. Is there a way to adjust the method to fix it? I don't want to have to state the class twice to get it to work.

[next sparrow]

I don't think so, because it's a problem not with the method itself, but with the RType enum

[high lodge]

So how to fix that

[next sparrow]

public class RType<T> implements IRType<T> {
    public static final RType<String> STRING = new RType<>(String.class, s -> s + " :)");
    public static final RType<Boolean> BOOLEAN = new RType<>(Boolean.class, b -> !((Boolean) b));
    public static final RType<Integer> INTEGER = new RType<>(Integer.class, i -> (int) i + 5);
 
    private final Class<?> dataType;
    private final Function<Object, Object> processRequest;
 
    RType(Class<?> dataType, Function<Object, Object> processRequest) {
        this.dataType = dataType;
        this.processRequest = processRequest;
    }
 
    @Override
    public Class<Object> getDataType() {
        return (Class<Object>) dataType;
    }
 
    public String getName() {
        return super.toString();
    }
 
    @Override
    public Object processRequest(Object requestData) {
        return null;
    }
 
    @Override
    public String toString() {
        return "RType{dataType=" + dataType + ", name=" + getName() + "}";
    }
}

[next sparrow]

So there're three individual static variables and each one has its own type and own generic type as it comes, therefore everything should work fine

God, why is it so hard to type on phone, it just freezes every few seconds 😭

@high lodge

[high lodge]

Ye I'm on phone too

And that kinda defeats the purpose of the enum. If it's the hard then I guess I'll just use strings for identifiers.

[next sparrow]

It's not hard, it's still the same enum, but with a separate variable for each element. You can still do RType.INTEGER, RType.BOOLEAN and such, everyone might not even understand that it's not an enum, before looking into RType implementation lol

Except it will work, and work beautifully with datatype checks from java compiler

[high lodge]

Cool

I meant because this is for server-client stuff, so it will need to be serializable, any ideas on a method that can get the variable name?

Actually better idea: integer id

[next sparrow]

I recommend you to look into Java reflection, there must be a method for that

[high lodge]

What is java reflection?

[next sparrow]

A bunch of classes and methods used to gain information about the structure of Java program itself. You already used one of its features: Class<T>

[high lodge]

oh

just asked chat gpt so I think I understand more

looks cool

thank you

[dull sluice]

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[next sparrow]

and powerful

You're welcome