Java Generics Puzzler, extending a class and using wildcards

Question

I\'ve been beating my head against this one for awhile and thought that maybe some fresh eyes will see the issue; thanks for your time.

import java.util.*;

clas         


        

Answer 1

OK, here's the answer:

import java.util.*;

class Tbin extends ArrayList {}
class TbinList extends ArrayList> {}

class Base {}
class Derived extends Base {}

public class Test {
  public static void main(String[] args) {

    TbinList test3 = new TbinList<>();
    test3.add(new Tbin());

  }
}

As I expected, kind of obvious once I saw it. But a lot of thrashing around to get here. Java generics seem simple if you only look at working code.

Thanks, everyone, for being a sounding board.