If I define in Kotlin List<Int> in java is e...

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[jdiaz]

If I define in Kotlin List<Int> in java is expecting List<? extends Integer>, what's the way of maintaining compatibility?

[snrostov]

Looks like MutableList<Int> in kotlin is same as java List<Int>.

Btw, List<Int> in java can be treated as one of this types in Kotlin:
- List<Int>
- List<Int>?
- List<Int?>
- List<Int?>?
- MutableList<Int>
- MutableList<Int>?
- MutableList<Int?>
- MutableList<Int?>?

[Andreas Sinz]

@jdiaz what do you mean with compatibility?

[dragas]

The following in kotlin

class KTesty
{
    fun foo(bar : Int)  {   }
}

is compiled into this in java

public final class KTesty {
   public final void foo(int bar) {
   }
}

[dragas]

Interestingly enough, you can't pass primitive values as generics in java, as a result, when when you compile the following in kotlin

val list = ArrayList<Int>()
list.add(bar)
val result = list[0]

You get this in java

ArrayList list = new ArrayList();
list.add(bar);
Integer result = (Integer)list.get(0);

[dragas]

Anyways, you shouldn't worry about java -> kotlin or kotlin -> java calls, as both of them are interchangeable.