Accessing primitives as references

[reef maple]

I've got a bit of a weird problem. I have some primitives (doubles, integers, booleans) that I need to access via reference. I'm making an automatic config system, and it's designed to work with just one function per parameter, addConfigParameter(key, variable), and anytime the reload function is called it should change variable based on the config file. This is possible if I use a reference type, but I'd like it to work for any code so hard coding configurable classes is a no-no. Anyone know of a way I can do this? I tried using the primitive wrapper classes Double vs double but it didn't seem to help.

[vagrant narwhal]

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[lament prism]

Double should have worked what the problem you are facing? any examples?

[river ermine]

Wrappers are immutable, so that's why they don't work too

[reef maple]

Yea, this is the code I create the parameter with

Double val = 1.0;
AutoConfig conf = new AutoConfig();
conf.addConfigValue("testconf", val);```

Then I set it with 
```java
private void setValue(Object obj, String key, YamlMapping map){
        if(obj instanceof Double){
            obj = map.doubleNumber(key);
        }```

which I've confirmed runs before I log the value, and map.doubleNumber(key) returns 42, but when I log val it's stil 1.0

I guess I could just create a class that holds a value and use that so I can get a reference to it but I feel like theres a better way than creating a class for every type of parameter I might use

[river ermine]

basically, that's bad approach, since java arguments are passed as values always. Consider refactoring your code in a way, that method returns object, and then you assign it to a neened variable.

[river ermine]

creating your own wrapper is the solution. And to avoid creating class for each type, you should use generics

like, ```java
class MyWrapper<T> {
T element;
public void setElement(T el) {
element = el;
}

public T getElement() {
return element;
}
}```

[reef maple]

Alright, tysm

I'll give it a go

[river ermine]

you are welcome

[reef maple]

That seems to work how I want, thanks again!

[vagrant narwhal]

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