This program gives a strange error message:

import java.util.*;
 
class Test {
    void test() {
        Object o = new ArrayList<? extends Number>();
    }
}

Test.java:5: unexpected type
found : ? extends java.lang.Number
required: class or interface without bounds
        Object o = new ArrayList<? extends Number>();
                                ^
1 error

This error message is for situations like this:

new String<Number>()

String is not a generic class and the error message
would be appropriate.