import java.util.List; import java.util.ArrayList; class Clazz { void foo(List<? extends Number> l) { boolean b = l.contains(<warning descr="'List<capture of ? extends Number>' may not contain objects of type 'String'">""</warning>); } void bar() { List<? extends Class<?>> l = new ArrayList<Class<?>>(); Class<?> o = String.class; int i = l.indexOf(o); } }