Question

in C#

class ListMap<K, E>
    : ImyMap<K, E>, IComparable<K>, IEnumerable<KeyValuePair<K, E>>
{
}

in Java

class MyListMap<K extends Comparable<? super K>, E>
    implements MyMap<K,E>, Iterable<KeyValuePair<K, E>>
{
}

Just trying to convert some data structures from Java into C# and wanted to know if my C# implementation is equal to my Java one.

If not can you please correct it?

Answer 1

No, those are not equal. The K extends ... portion needs to be translated into a constraint:

class ListMap<K, E>
    : ImyMap<K, E>, IEnumerable<KeyValuePair<K, E>>
   where K : IComparable<K>
{
}

The wildcard ? super K is not necessary in C#. Wildcards are Java’s way to support co/contravariance. In C#, this is done as part of the interface declaration:

interface IComparable<in K> { ... }

The in modifier makes the interface contravariant, which has the same effect as the wildcard in Java.