This lab will be dealing with linked list. Please read carefully Construct a jav

Question

This lab will be dealing with linked list. Please read carefully

Construct a java program that will retrieve, update and manipulate a small payroll database.

Note that each line in the file, payfile.txt, contains a field for

- firstName

- lastName

- gender

- tenure

- rate

- salary

1. Read each line of data from payfile.txt, place the data into an Employe object, and insert the Employee object onto the end of an ObjectList.

2. Traverse the list and output the contents of the info field of each ObjectListNode into an easily read table format with each field appropriatley labeled.

3. Traverse the list and output the contents of the info field of each ObjectListNode into an easily read table format with each field appropriately.

4. Traverse the list and output the number of employees.

5. Traverse the list and output the first name of all women on payroll

6. Traverse the list and output the first and last names and salary of all weekly employees who make more than $35,000 per year year and who have been with the company for at least five years.

7. Traverse the list and give a raise of $0.75 per hour to all employees who are paid on an hourly basis and make less than $10.00 per hour; and give a raise of $50.00 per week to all employees who are paid on a weekly basis and make less than $350.00 per week. Be sure to output the first and last names and new salaries for each employees on the payroll who has recieved a raise.

8. Sort the nodes of the linked list into alphabetical order according to last name and print the first and last names and salaries for each employee on the payroll.

9. The file hirefile.txt conatins data for three employees to be hired by the company. Insert each of the new employees into the correct location in the sorted linear linked list and print the first and last names for each employee on the payroll.

10. The firefile.txt contains data for two employees to be fired by the company. Delete the corresponding nodes in the sorted linear linked list for each of the employees to be fired and print the first and last names for each employee on the payroll.

Leave comments on your codes as well.

Use ObjectListNode and ObjectList classes as well as the Comparable interface to allow you to make appropriate comparisons in the ObjectList class.

Your program should use at least the following classes

- ObjectListNode

- ObjectList

- Comparable

- Driver (main class)

- Payroll

- Employee

Here is a diagram below

Codes given

hirefile.txt

firefile.txt

Explanation / Answer

public class ObjectListNode {
private Object info;
private ObjectListNode next;
  
// Default ctor
public ObjectListNode() {
info = null;
next = null;
}

// One-arg ctor
public ObjectListNode (Object o) {
info = o;
next = null;
}
  
// Two-arg ctor
public ObjectListNode (Object o, ObjectListNode p) {
info = o;
next = p;
}   

// Sets info field
public void setInfo(Object o) {
info = o;
}

// Returns object in info field
public Object getInfo() {
return info;
}

// Sets next field
public void setNext(ObjectListNode p) {
next = p;
}

// Returns object in info field
public ObjectListNode getNext() {
return next;
}
}

// ObjectList.java

public class ObjectList implements ObjectListInterface{
private ObjectListNode list;
private ObjectListNode last;
  
// Constructs an empty list
public ObjectList() {
list = null;
last = null;
}

// Returns the first node in the list
public ObjectListNode getFirstNode() {
return list;
}
  
// Returns the last node in the list
public ObjectListNode getLastNode() {
return last;
}

// Returns the first object in the list
public Object getFirst() {
if (list == null) {
System.out.println("Runtime Error: getFirst()");
System.exit(1);
}
return list.getInfo();
}

// Returns the last object in the list
public Object getLast() {
if (list == null) {
System.out.println("Runtime Error: getLast()");
System.exit(1);
}
return last.getInfo();
}

// Adds an object to the front of a list
public void addFirst(Object o) {
ObjectListNode p = new ObjectListNode(o, list);
if (list == null)
last = p;
list = p;
}

// Adds a node to the front of the list
public void addFirst(ObjectListNode p) {
if (p == null) {
System.out.println("Runtime Error: addFirst()");
System.exit(1);
}
p.setNext(list);
if (list == null)
last = p;
list = p;
}
  
// Adds an object to the end of the list
public void addLast(Object o) {
ObjectListNode p = new ObjectListNode(o);
if (list == null)
list = p;
else
last.setNext(p);
last = p;
}

// Adds a node to the end of the list
public void addLast(ObjectListNode p) {
if (p == null) {
System.out.println("Runtime Error: addLast()");
System.exit(1);
}
p.setNext(null);
if (list == null)
list = p;
else
last.setNext(p);
last = p;
}

// Removes the first object from the list
public Object removeFirst() {
if (list == null) {
System.out.println("Runtime Error: removeFirst()");
System.exit(1);
}
ObjectListNode p = list;
list = p.getNext();
if (list == null)
last = null;
return p.getInfo();
}

// Removes the last object from the list
public Object removeLast() {
if (list == null) {
System.out.println("Runtime Error: removeLast()");
System.exit(1);
}
ObjectListNode p = list;
ObjectListNode q = null;
while (p.getNext() != null) {
q = p;
p = p.getNext();
}
if (q == null) {
list = null;
last = null;
}
else {
q.setNext(null);
last = q;
}
return p.getInfo();
}

// Inserts an object after the node referenced by p
public void insertAfter (ObjectListNode p, Object o) {
if (list == null || p == null) {
System.out.println("Runtime Error: insertAfter()");
System.exit(1);
}
ObjectListNode q = new ObjectListNode(o, p.getNext());
p.setNext(q);
if (q.getNext() == null)
last = q;
}

// Inserts a node after the node referenced by p
public void insertAfter(ObjectListNode p, ObjectListNode q) {
if (list == null || p == null || q == null) {
System.out.println("Runtime Error: insertAfter()");
System.exit(1);
}
q.setNext(p.getNext());
p.setNext(q);
if (last.getNext() != null)
last = q;
}

// Deletes the node after the node referenced by p
public Object deleteAfter(ObjectListNode p) {
if (list == null || p == null || p.getNext() == null) {
System.out.println("Runtime Error: deleteAfter()");
System.exit(1);
}
ObjectListNode q = p.getNext();
p.setNext(q.getNext());
if (p.getNext() == null)
last = p;
return q.getInfo();
}

// Inserts an item into its correct location within an ordered list
public void insert(Object o) {
ObjectListNode p = list;
ObjectListNode q = null;
while (p != null && ((Comparable)o).compareTo(p.getInfo()) > 0) {
q = p;
p = p.getNext();
}
if (q == null)
addFirst(o);
else
insertAfter(q, o);
}

// Inserts a node into its correct location within an ordered list
public void insert(ObjectListNode r) {
ObjectListNode p = list;
ObjectListNode q = null;
while (p != null &&
((Comparable)r.getInfo()).compareTo(p.getInfo()) > 0) {
q = p;
p = p.getNext();
}
if (q == null)
addFirst(r);
else
insertAfter(q, r);
}

// Removes the first occurrence of an item in a list
public Object remove(Object o) {
ObjectListNode p = list;
ObjectListNode q = null;
while (p != null && ((Comparable)o).compareTo(p.getInfo()) !=
0) {
q = p;
p = p.getNext();
}
if (p == null)
return null;
else return q == null ? removeFirst() : deleteAfter(q);
}

// Returns true if the item is found in the list
public boolean contains(Object o) {
ObjectListNode p = list;
while (p != null && ((Comparable)o).compareTo(p.getInfo()) !=
0)
p = p.getNext();
return p != null;
}

  
// Returns a reference to the node with the requested value
// Returns null otherwise
public ObjectListNode select(Object o) {
ObjectListNode p = list;
while (p != null)
if (((Comparable)o).compareTo(p.getInfo()) == 0)
return p;
else
p = p.getNext();
return null;
}

// Determines whether or not a list is empty
public boolean isEmpty() {
return list == null;
}

// Removes all elements from a list
public void clear() {
list = null;
last = null;
}

// Returns the number of elements in the list
public int size() {
int count = 0;
ObjectListNode p = list;
while (p != null) {
++count;
p = p.getNext();
}
return count;
}

// Makes a copy of a list
public ObjectList copyList() {
ObjectListNode p = null;
ObjectListNode q = null; // to satisfy compiler;
ObjectListNode r = list;
  
if (isEmpty())
return null;
ObjectList newList = new ObjectList();
while (r != null) {
p = new ObjectListNode(r.getInfo());
if (newList.isEmpty())
newList.addFirst(p);
else
q.setNext(p);
q = p;
r = r.getNext();
}
newList.last = p;
return newList;
}
  
// Reverses a list
public void reverse() {
ObjectListNode p = list;
ObjectListNode q = null;
ObjectListNode r;
  
while (p != null) {
r = q;
q = p;
p = p.getNext();
q.setNext(r);
}
last = list;
list = q;
}   
}

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