CMSC132 Summer 2018

Doubly Linked Lists

Overview

For this project you will implement a basic doubly linked and a sorted doubly linked list. Notice that no public tests are part of this project as all tests are either release or secret.

Objectives

This project will allow you practice doubly linked lists and testing.

Grading

• (40%) Release Tests
• (50%) Secret Tests
• (10%) Style

Clarifications

Any clarifications or corrections associated with this project will be available at Project Clarifications.

Code Distribution

The project's code distribution is available by checking out the project named LinkedListsProject. The code distribution provides you with the following:

• listClasses package → Where classes implementing linked lists will appear.
• tests package → Where you should place your student tests.

Specifications

• You are expected to implement two classes: BasicDoubleLinkedList and SortedDoubleLinkedList.The javadoc describing what you need to implement can be found at Project Javadoc.
• The linked list in our project has a head and tail reference. The next link of the last node points to null.
• Methods addToEnd(), getLast(), retrieveLastElement() rely (and must use) the tail reference.
• The head and tail must be set correctly when list operations update the list.
• Your code must be efficient. For example, you will lose credit if you perform an unnecessary list traversal(s) during the implementation of a method. Keep in mind this is a doubly linked list.
• If you see in the submit server the error "missing_component", the problem is that you are missing a required class. You can also get this error if you are not defining a generic class correctly. For example, your SortedLinkedList class is not being defined as expected. It is recommended that you try submitting your project immediately (if you have not done so yet) so you can identify this problem (your code may work in Eclipse but not in the submit server).

Requirements

• You may not use recursion in this project.
• For this project you are not required to write student tests, but you are strongly encourage to do so. If you have a problem with your code and need assistance during office hours, you need to have a student test(s) that illustrates the problem you are experiencing. See Student Tests for information regarding the implementation of student tests.
• The iterator you define may NOT be used to implement other list operations (e.g., add). The iterator is for users that want to iterate over the list.
• You need to implement a doubly-linked list that relies on a head and tail reference.
• See Style Guidelines for information regarding style.

Sample Driver

The following driver and associated output provide an idea of the classes you need to implement.

package tests;

import listClasses.BasicDoubleLinkedList;
import listClasses.SortedDoubleLinkedList;

public class SampleDriver {

	public static void main(String[] args) {
		BasicDoubleLinkedList < String > basicList = new BasicDoubleLinkedList();

		basicList.addToEnd("Red").addToFront("Yellow").addToFront("Blue");
		System.out.println("First: " + basicList.getFirst());
		System.out.println("Last: " + basicList.getLast());
		System.out.println("Size: " + basicList.getSize());
		System.out.println("Retrieve First: " + basicList.retrieveFirstElement());
		System.out.println("Retrieve Last: " + basicList.retrieveLastElement());
		System.out.println("Removing Red");
		basicList.remove("Red", String.CASE_INSENSITIVE_ORDER);
		System.out.print("Iteration: ");
		for (String entry : basicList) {
			System.out.print(entry + " ");
		}
		
		SortedDoubleLinkedList sortedList = new SortedDoubleLinkedList(String.CASE_INSENSITIVE_ORDER);
		sortedList.add("Yellow").add("Red");
		System.out.print("\n\nIteration (for sorted list): ");
		for (String entry : sortedList) {
			System.out.print(entry + " ");
		}
		sortedList.remove("Red");
		System.out.print("\nAfter remove in sorted list first is: ");
		System.out.println(sortedList.getFirst());
	}
}


Output

First: Blue
Last: Red
Size: 3
Retrieve First: Blue
Retrieve Last: Red
Removing Red
Iteration: Yellow 

Iteration (for sorted list): Red Yellow 
After remove in sorted list first is: Yellow