Linked Data Structure

Question 1

The linked list constructor sets the head instance variable to a reference to an empty node.

Answer 1

False - head is set to null.

Question 2

Erasing a reference to a node always results in it being deleted by the garbage collector.

Answer 2

False - only if there aren’t any other references to it.

Question 3

The method deleteHeadNode() removes the first node from the list, and head now points to what was the second node in the list.

Answer 3

True.

Question 4

A node inner class should be defined as private, unless used elsewhere.

Answer 4

True.

Question 5

How many attributes are there (at minimum) in the node class of a doubly linked list?

Answer 5

3

Question 6

When can a generic linked list use the clone method to create a deep copy?

Answer 6

If the type parameter is bounded such that the type must implement a custom interface, which itself extends cloneable and makes the clone() method public (instead of protected).

Question 7

Define the head attribute of a generic linked list.

Answer 7

private Node<T> head;</T>

Question 8

To define an equals() method for a generic linked list, equals() must be defined for the type parameter T.

Answer 8

True.

Question 9

If a non-generic class called LinkedList2 has an inner (non-static) iterator class called Iterator2, how would you construct an instance of this iterator in the driver?

Answer 9

LinkedList2 list = new LinkedList2();
LinkedList2.Iterator2 i = list.new Iterator2();

Question 10

What are the 3 basic methods defined in and used by an Iterator class?

Answer 10

A restart, hasNext and next method.

Question 11

Java has an Iterator interface that specifies how Java would like an iterator to behave.

Answer 11

True.