IN JAVA

Instructions

Your goal in this assignment is to implement LinkedList class invert method. As the name suggests, the invert method should reverse the order of elements in the original list. For example, if the original list is 1, 2, 3, after calling invert the list should read 3, 2, 1.

I WILL POST THE CODE FOR EACH CLASS BELOW

LinkedList.java

public class LinkedList {
	private Node head;
	public LinkedList() {
	head = null;
	}
	// add in front
	public void add(int data) {
	Node newNode = new Node(data);
	newNode.setNext(head);
	head = newNode;
	}
	// add tail
	public void append(int data) {
	Node newNode = new Node(data);
	if (isEmpty())
	head = newNode;
	else {
	Node current = head;
	while (current.getNext() != null)
	current = current.getNext();
	current.setNext(newNode);
	}
	}
	@Override
	public String toString() {
	String out = "";
	Node current = head;
	while (current != null) {
	out += current.toString() + " ";
	current = current.getNext();
	}
	return out;
	}
	public boolean isEmpty() {
	return head == null;
	}
	public int size() {
	int count = 0;
	Node current = head;
	while (current != null) {
	count++;
	current = current.getNext();
	}
	return count;
	}
	public int get(int index) {
	if (index < 0 || index >= size())
	return 0;
	int i = 0;
	Node current = head;
	while (i < index) {
	i++;
	current = current.getNext();
	}
	return current.getData();
	}
	public void set(int index, int data) {
	if (index < 0 || index >= size())
	return;
	int i = 0;
	Node current = head;
	while (i < index) {
	i++;
	current = current.getNext();
	}
	current.setData(data);
	}
	void insert(int index, int data) {
	if (index < 0 || index >= size())
	return;
	if (index == 0)
	add(data);
	else {
	Node newNode = new Node(data);
	int i = 0;
	Node current = head;
	while (i < index - 1) {
	i++;
	current = current.getNext();
	}
	newNode.setNext(current.getNext());
	current.setNext(newNode);
	}
	}
	void remove(int index) {
	if (index < 0 || index >= size())
	return;
	if (index == 0) {
	Node temp = head;
	head = head.getNext();
	temp.setNext(null);
	}
	else {
	int i = 0;
	Node current = head;
	while (i < index - 1) {
	i++;
	current = current.getNext();
	}
	Node temp = current.getNext();
	current.setNext(current.getNext().getNext());
	temp.setNext(null);
	}
	}
	}

LinkedListDriver.java

import com.sun.security.jgss.GSSUtil;
	public class LinkedListDriver {
	public static void main(String[] args) {
	LinkedList ll = new LinkedList();
	ll.append(3);
	// ll.append(5);
	// ll.append(8);
	// ll.append(2);
	System.out.println(ll);
	ll.remove(0);
	System.out.println(ll);
	System.out.println(ll.isEmpty());
	}
	}

LinkedListTest.java

import org.junit.jupiter.api.Test;
	import javax.sound.sampled.Line;
	import static org.junit.jupiter.api.Assertions.*;
	class LinkedListTest {
	@Test
	public void testListEmpty() {
	LinkedList ll = new LinkedList();
	assertTrue(ll.isEmpty());
	assertEquals(0, ll.size());
	}
	@Test
	public void testListNotEmpty() {
	LinkedList ll = new LinkedList();
	ll.add(5);
	assertFalse(ll.isEmpty());
	assertNotEquals(0, ll.size());
	}
	@Test
	public void testListThreeFiveEight() {
	// create the scenario 3, 5, 8
	LinkedList ll = new LinkedList();
	ll.append(3);
	ll.append(5);
	ll.append(8);
	// do the assertions with isEmpty, size, get
	assertFalse(ll.isEmpty());
	assertEquals(3, ll.size());
	assertEquals(3, ll.get(0));
	assertEquals(5, ll.get(1));
	assertEquals(8, ll.get(2));
	}
	@Test
	public void testListThreeFiveEightInsertTenBtwThreeFive() {
	// create the scenario 3, 5, 8
	LinkedList ll = new LinkedList();
	ll.append(3);
	ll.append(5);
	ll.append(8);
	ll.insert(1, 10);
	// do the assertions with isEmpty, size, get
	assertFalse(ll.isEmpty());
	assertEquals(4, ll.size());
	assertEquals(3, ll.get(0));
	assertEquals(10, ll.get(1));
	assertEquals(5, ll.get(2));
	assertEquals(8, ll.get(3));
	}
	}

NODE.java

public class Node {
	private int data;
	private Node next;
	public Node() {
	data = 0;
	next = null;
	}
	public Node(int data) {
	this.data = data;
	next = null;
	}
	public int getData() {
	return data;
	}
	public Node getNext() {
	return next;
	}
	public void setData(int data) {
	this.data = data;
	}
	public void setNext(Node next) {
	this.next = next;
	}
	@Override
	public String toString() {
	return data + "";
	}
	}