Netbeans - Java

1- Write a Stack class. This class should use your LinkedList class. Your stack should hold integers. It must contain the following methods:

Stack() Default constructor

push(valueToAdd) Adds a new element to the top of the

stack pop() Removes the element from the top of the stack and returns its value.

getHeight() Returns the height of the stack.

display() Displays the stack and its contents.

It should display the top element first. See output below for an example.

2- Write a Queue class. This class should use your LinkedList class.

Your queue should hold integers. It must contain the following methods:

Queue() Default constructor

enqueue(valueToAdd) Adds a new element to back of the queue

dequeue() Removes the element from the front of the queue and returns its value.

getLength() Returns the length of the

queue. display() Displays the queue and its contents.

It should display the first element in the queue first. See output below for an example.

I already have the linked list that is this one:

This linked list implementation should be in its own class named LinkedList. Your linked list should hold integers. It must contain the following methods:

Default constructor Creates a new node and adds it to the front of the linked list.

Removes the front node from the linked list and returns the value it contained. Creates a new node and adds it to the back of the linked list.

Removes the last node from the linked list and returns the value it contained. Returns the length of the linked list

Displays the linked list and its contents.

############ LinkedList.java ############

class NodeList {

int data;

NodeList next;

public NodeList(int data) {

this.data = data;

next = null;

}

}

public class LinkedList {

private NodeList head;

private int size;

public LinkedList() {

head = null;

size = 0;

}

public void addFront(int data) {

NodeList newNode = new NodeList(data);

newNode.next = head;

head = newNode;

size = size+1;

}

public int removeFront(){

if(head == null){

System.out.println("List is empty");

return -999;

}

int value = head.data;

head = head.next;

size = size-1;

return value;

}

public void addBack(int value){

if(head == null){

head = new NodeList(value);

}else{

NodeList temp = head;

while(temp.next != null)

temp = temp.next;

temp.next = new NodeList(value);

}

size = size+1;

}

public int removeBack(){

// list is empty

if(head == null){

System.out.println("List is empty");

return -999;

}

// only one node

if(head.next == null){

int value = head.data;

head = null;

return value;

}

NodeList temp = head;

while(temp.next.next != null)

temp = temp.next;

int value = temp.next.data;

temp.next = null;

size = size-1;

return value;

}

public int getLength(){

return size;

}

public void display(){

NodeList temp = head;

while(temp != null){

if(temp.next!=null)

System.out.print(temp.data+"-->");

else

System.out.println(temp.data);

temp = temp.next;

}

System.out.println();

}

}

############# LinkedListTest.java ################

public class LinkedListTest {

public static void main(String[] args) {

LinkedList list = new LinkedList();

System.out.println("Adding elements to the front......");

list.addFront(8);

list.display();

list.addFront(33);

list.display();

list.addFront(58);

list.display();

System.out.println("Length of linked list: "+list.getLength());

System.out.println();

System.out.println("Adding elements to the back......");

list.addBack(1);

list.display();

list.addBack(34);

list.display();

list.addBack(20);

list.display();

System.out.println("Length of linked list: "+list.getLength());

System.out.println();

System.out.println("Removing elements from the front.....");

list.removeFront();

list.display();

list.removeFront();

list.display();

System.out.println("Length of linked list: "+list.getLength());

System.out.println();

System.out.println("Removing elements from the back.....");

list.removeBack();

list.display();

list.removeBack();

list.display();

System.out.println("Length of linked list: "+list.getLength());

System.out.println();

}

}

/*

Sample run:

Adding elements to the front......

8

33-->8

58-->33-->8

Length of linked list: 3

Adding elements to the back......

58-->33-->8-->1

58-->33-->8-->1-->34

58-->33-->8-->1-->34-->20

Length of linked list: 6

Removing elements from the front.....

33-->8-->1-->34-->20

8-->1-->34-->20

Length of linked list: 4

Removing elements from the back.....

8-->1-->34

8-->1

Length of linked list: 2

*/

Linked List Adding elements to the front. 33 8 58 >33 8 Length of linked list: 3 Adding elements to the back. 58 >33 58 >33- 8-- 1-- 34 58 >33 Length of linked list: 6 Removing elements from the front... 33 8- 1 -->34 ->20 Length of linked list: 4 Removing elements from the back. >34 >1 >1 Length of linked list: 2 Stack Pushing elements 33 8 58- 33- 8 Height of stack: 3 Popping elements Popped: 58 33 >8 Popped: 33 Popped: 8 Queue 17 >17 102-- 17- 2 Length of queue: 3 De queued: 2 102- 17 De queued: 17 Dequeued: 102