Computer scienceProgramming languagesJavaCode organizationGeneric programmingGenerics essentials

Type Bounds

The result of the code

Report a typo

Take a look at this piece of code:

public class Application<T> {
  
  public static void main(String[] args) {
    
    Application<Number> application = new Application<>();
    Number n1 = application.typeBoundsTest(Integer.valueOf(10));
    Number n2 = application.typeBoundsTest(Double.valueOf(1.0));
    
    System.out.println(String.format("%s %s", n1, n2));

  }
  
  public <T1 extends T> T typeBoundsTest(T1 item) {
    return item;
  }

}

What will be the result of its compilation and execution?

Note, that both Integer and Double (as well as some other wrapper classes like Float, Long, etc.) are subclasses of an abstract class Number.

Select one option from the list

Runtime error

It compiles and prints "10 1.0"

Compile-time error "The method typeBoundsTest(T1) in the type Application<Number> is not applicable for the arguments"

Compile-time error "Type mismatch"

Compile-time error "The type T is not an interface; it cannot be specified as a bounded parameter"

___

Create a free account to access the full topic