T4.java:12: error: cannot find symbol
		T4<String> t = new BlackStripe<String, x>();
		                                       ^
  symbol:   class x
  location: class T4<String>
  where String is a type-variable:
    String extends Object declared in class T4
T4.java:12: error: incompatible types
		T4<String> t = new BlackStripe<String, x>();
		               ^
  required: T4<String>
  found:    T4<String>.BlackStripe<String,x>
  where String is a type-variable:
    String extends Object declared in class T4
2 errors
