Why I do hate java

Ref.java

public class Ref {
    public void inc1(int i) {
        ++i;
    }
    public void inc2(Integer i) {
        ++i;
    }
    public static void main(String[] args) {
        int foo = 32;
        Integer bar = 41;
        Ref r = new Ref();
        System.out.println("Expected: 32x41\nGot: " + foo + "x" + bar);
        r.inc1(foo);
        System.out.println("Expected: 32x41\nGot: " + foo + "x" + bar);
        r.inc2(bar);
        System.out.println("Expected: 32x42\nGot: " + foo + "x" + bar);
        r.inc1(bar);
        System.out.println("Expected: 32x42\nGot: " + foo + "x" + bar);
        r.inc2(foo);
        System.out.println("Expected: 32x42\nGot: " + foo + "x" + bar);
        /* Output:
Expected: 32x41
Got: 32x41
Expected: 32x41
Got: 32x41
Expected: 32x42
Got: 32x41
Expected: 32x42
Got: 32x41
Expected: 32x42
Got: 32x41
        */
    }
}

public void inc2(Integer i) {
try {
f = i.getClass().getDeclaredField("value");
f.setAccessible(true);
f.set(i, i+1);
} catch (NoSuchFieldException e) {
e.printStackTrace(); //To change body of catch statement use File | Settings | File Templates.
} catch (IllegalAccessException e) {
e.printStackTrace(); //To change body of catch statement use File | Settings | File Templates.
}
}

loljava

This makes perfect sense, really… “int” is a basic type, and is therefore passed by value. “Integer” is an object (basically an object wrapper around an int), and is therefore passed by reference, like any other Java object.

Yep, I totally agree, but that is actually my point, when passing an Integer to a method which takes as parameter an Integer, a reference is passed, but changing the value of the Integer with the ++ operator creates a new Integer and thus does not modify the Integer it was given. That kinda sucks not to be able to do such a thing without using the reflection API ...
In this case there is no big deal, I can return i; at the end, but if I want a method with two in-out Integers, I'm stuck and have to make them fields of a class which I will pass, and that's not handy at all. I really prefer the vala or C way for exemple, for this kind of stuff

Oh, I see… I wasn’t quite paying enough attention. Yes, it is odd how Integer is an effectively immutable object like that, which is different from most other Java objects.
I’m not a particularly big fan of Java myself, or I might have noticed that sooner ☺