Why isnt java.io being used ?

[bdl1127]

I am using import.java.io.*; at the beginning of my code so that I can write my own exceptions. However, after compiling my program, I am getting a warming claiming that java.io is not being used. When running the Remove() method in my Tester class, I get unhandled exception errors. Any insight? TIA

Here are the static classes I wrote to create the methods:

  public static class ListEmptyException extends Exception {
    public ListEmptyException(String s)
    {super (s);}
}
  
  public static class NotInListException extends Exception {
    public NotInListException(String s)
    {super (s);}
  }

And here is the method that I want to throw them in:

public void remove(Comparable d) throws ListEmptyException, NotInListException{
    
    Node<Comparable> previous, traverse;
    
    if(empty()) 
      throw new ListEmptyException("empty when removed");
    
    previous = head;
    traverse = head.next;
    
    while(traverse != null && !traverse.data.equals(d)) {
      previous = traverse;
      traverse = traverse.next;
    }
    
    if(traverse == null)
      throw new NotInListException("Item is not in the list");
    
    if(previous == null) {
      traverse = traverse.next;
    } else {
      previous.next = traverse.next;
      size--;
    }
  }

[Fubarable]

Why do you think that java.io.*; should be used? What io classes do you think that you are using in your code?

[bdl1127]

Why do you think that java.io.*; should be used? What io classes do you think that you are using in your code?

dont I need java.io to create and throw exceptions?

[bdl1127]

here is the code in the main of my Tester class, if it makes a difference..

 try {
   numbers.remove(10);
  } catch (ListEmptyException e) {
   System.out.println(e.getMessage() +"OK: The list is empty");
  } catch (NotInListException e) {
   System.out.println("WRONG: This should not happen");
  }

[Fubarable]

dont I need java.io to create and throw exceptions?

Have you first looked at the API for the Exception and the Throwable classes to see what is required for their use? It's all there in the API. See if they are declared as java.io.Exception and java.io.Throwable? They're not.

[bdl1127]

This is pretty much exactly how it was shown to us in notes, and the Tester class was provided to us. Are my static classes correct? What needs to be changed?

[Fubarable]

What happens when you test your code with code that should result in the exceptions being thrown? Does it work as expected? What about when you use code that should work well? Does the code still work as expected? One proof of its validity (admittedly only a partial proof) is in its functioning.