Notes

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.Scanner;

public class HumanResources {
static ArrayList<Staff> listStaff = new ArrayList<Staff>(); // Create a new ArrayList named listStaff from the Staff class
static ArrayList<Department> listDepartment = new ArrayList<Department>(); // Create a listDepartment ArrayList to store 3 options for the Department
static Scanner console = new Scanner(System.in);

// Main Method
public static void main(String[] args) {

// First Initiate - Create 3 objects in Department class for 3 different departments
Department d1 = new Department("d01", "Business Department", 0);
listDepartment.add(d1);
Department d2 = new Department("d02", "Project Department", 0);
listDepartment.add(d2);
Department d3 = new Department("d03", "Technical Department", 0);
listDepartment.add(d3);

// Entering Console Interface
int choose;
do {
showMenu();
// Checking the user input is valid from 0 to 10
while (true) {
System.out.println("Please type a number from 0 to 9 to run our program: ");
//choose = Integer.parseInt(console.nextLine());
if (console.hasNextInt()){ // User type in an integer
choose = console.nextInt();
console.nextLine(); // clear console
if (choose < 0 || choose > 10) {
System.err.println("You should type a number between 0 and 9!");
} else {
break; // choose successfully passed
}
} else { // User type in a String
System.err.println("You should type a number!");
console.nextLine(); // clear console
}
}

// user input choose pass the condition, now choose is ranging from 0 to 10
switch (choose) {
case 1: //1. Showing all the staff's names.
displayAllStaff();
break;
case 2: //2. Showing all the departments in the company.
displayAllDepartment();
break;
case 3: //3. Showing all the staff's names in each department.
displayStaffInEachDep();
break;
case 4: //4. Adding a new employee.
inputEmployee();
break;
case 5: //5. Adding a new manager.
inputManager();
break;
case 6: //6. Searching a staff's information based on a name.
searchNameStaff();
break;
case 7: //7. Searching a staff's information based on an id.
searchIdStaff();
break;
case 8: //8. Showing all the staff's salary.
displayAllSalary();
break;
case 9: //9. Sorting the staff's salary in ascending order.
sortSalaryAscending();
break;
case 10: //10. Sorting the staff's salary in descending order.
sortSalaryDescending();
break;
case 0: //0. Closing the Program.
System.out.println("Good bye!");
break;
}
} while (choose != 0);
}

// Show Menu Method
public static void showMenu() {
breakLine();
System.out.println("Welcome to our Human Resources Program, please choose one of the following numbers to run the program!");
System.out.println("1. Showing all the staff's names.");
System.out.println("2. Showing all the departments in the company.");
System.out.println("3. Showing all the staff's names in each department.");
System.out.println("4. Adding a new employee.");
System.out.println("5. Adding a new manager.");
System.out.println("6. Searching a staff's information based on a name.");
System.out.println("7. Searching a staff's information based on an id.");
System.out.println("8. Showing all the staff's salary.");
System.out.println("9. Sorting the staff's salary in ascending order.");
System.out.println("10. Sorting the staff's salary in descending order.");
System.out.println("0. Closing the Program.");
}

// Feature 1 - Showing all the staff's names
public static void displayAllStaff() {
breakLine();
System.out.println("LIST OF ALL THE STAFF: ");
for (int i = 0; i < listStaff.size(); i++) {
System.out.print(i + 1 + ". ");
listStaff.get(i).displayInformation();
System.out.println(); // Enter another line for another index in the list
}
}

// Feature 2 - Showing all the departments' in the company
public static void displayAllDepartment() {
breakLine();
System.out.println("LIST OF ALL THE DEPARTMENTS:");
for (int i = 0; i < listDepartment.size(); i++) {
System.out.print(i + 1 + ". ");
System.out.println(listDepartment.get(i).getNameDepartment()); // Display Department Name
}
}

// Feature 3 - Showing all the staff's names in each department
public static void displayStaffInEachDep() {
breakLine();
System.out.println("DISPLAY ALL THE STAFF IN EACH DEPARTMENT");
System.out.println();
// 1st Loop - Loop through listDepartment & Print the details
for (int i = 0; i < listDepartment.size(); i++) {
System.out.print(i + 1 + ". ");
System.out.println(listDepartment.get(i).getNameDepartment()); // Display the Department Name

int index = 0;
// 2nd Loop - Loop through listStaff to find the matching Staff in the same department & Print the details
for (int j = 0; j < listStaff.size(); j++) {
// If condition that an instance of listStaff which has the department property the same as the department
if (listStaff.get(j).getDepartment().idDepartment.equals(listDepartment.get(i).idDepartment)) {
index++;
System.out.print(i + 1 + ". " + index + ". "); // Display the index, i.e. 1.1, 1.2, 1.3, etc.
listStaff.get(j).displayInformation(); // this method already has the Println function to display the Staff's details
}
}
}
}

// Feature 4 - Adding new Employee Method
public static void inputEmployee() {
// Create a child object m_staff of the abstract class Staff with the Manager() package class
Staff m_staff = new Employee();

// 4.1 Employee ID Input
breakLine();
System.out.println("ADDING A NEW EMPLOYEE");
System.out.println("Please enter the employee's id: ");
while (true) {
String idStaffInput = console.nextLine();
boolean check = m_staff.setIdStaff(idStaffInput);
if (check) {
break;
}
}

// 4.2 Employee Name Input
System.out.println("Please enter the employee's name: ");
while (true) {
String nameStaffInput = console.nextLine();
boolean check = m_staff.setNameStaff(nameStaffInput);
if (check) {
break;
}
}

// 4.3 Employee Age Input
System.out.println("Please enter the employee's age: ");
while (true) {
int ageStaffInput = getInt(); // the getInt() method here to check whether the input is as an integer
boolean check = m_staff.setAgeStaff(ageStaffInput); // the setter here to check whether the input is a positive number
if (check) {
break;
}
}

// 4.4 Salary Weight Input
System.out.println("Please enter his/her salary weight: ");
while (true) {
int salaryWeightInput = getInt();
boolean check = m_staff.setSalaryWeight(salaryWeightInput);
if (check) {
break;
}
}

// 4.5 Starting Date Input
System.out.println("Please enter the employee's starting date: ");
String dateStartInput = console.nextLine();
while (!m_staff.setDateStart(dateStartInput)) {
System.err.println("Please enter as the Date format as dd/MM/yyyy");
dateStartInput = console.nextLine();
}

// 4.6 Department Choosing
System.out.println("List of Department: ");
System.out.println("Press 1 for Business Department.");
System.out.println("Press 2 for Project Department.");
System.out.println("Press 3 for Technical Department.");
System.out.println("Please choose the employee's department from one of three choices above: ");
// Choose 1 in 3 Department then that Department Staff quantity increases by 1
while (true) {
int departmentInput = getInt();
if (departmentInput == 1) { // User choose 1
// Set the property m_department in abstract class Staff to the 1st element of listDepartment arrayList
m_staff.setDepartment(listDepartment.get(0));
// Set the number Staff in Business Department increased by 1 in class Department
listDepartment.get(0).setNumberStaffDepartment(listDepartment.get(0).getNumberStaffDepartment() + 1);
break;
} else if (departmentInput == 2) { // User choose 2
// Set the property m_department in abstract class Staff to the 2nd element of listDepartment arrayList
m_staff.setDepartment(listDepartment.get(1));
// Set the number Staff in Project Department increased by 1 in class Department
listDepartment.get(1).setNumberStaffDepartment(listDepartment.get(1).getNumberStaffDepartment() + 1);
break;
} else if (departmentInput == 3) { // User choose 3
// Set the property m_department in abstract class Staff to the 3rd element of listDepartment arrayList
m_staff.setDepartment(listDepartment.get(2));
// Set the number Staff in Technical Department increased by 1 in class Department
listDepartment.get(2).setNumberStaffDepartment(listDepartment.get(2).getNumberStaffDepartment() + 1);
break;
} else {
System.err.println("Please enter only number 1, 2, or 3!");
}
}

// 4.7 Day Off Quantity Input
System.out.println("Please enter the employee's number of day off: ");
while (true) {
int dayOffQuantityInput = getInt();
boolean check = m_staff.setDayOffQuantity(dayOffQuantityInput);
if (check) {
break;
}
}

// 4.8 Overtime Hours Input
System.out.println("Please enter the employee's overtime hours: ");
while (true) {
int OTHoursInput = getInt();
boolean check = ((Employee) m_staff).setOTHours(OTHoursInput); // DownCasting the type of 'm_staff' in abstract class 'Staff' to 'Employee' class to get the properties in 'Employee'
if (check) {
break;
}
}

// Finishing filling all the properties of an object m_staff and save to the listStaff ArrayList with the next index
listStaff.add(m_staff);
}

// Feature 5 - Adding new Manager Method
public static void inputManager() {
// Create a child object m_staff of the abstract class Staff with the Manager() package class
Staff m_staff = new Manager();

// 5.1 Manager ID input
breakLine();
System.out.println("ADDING A NEW MANAGER");
System.out.println();
System.out.println("Please enter the manager's id");
while (true) {
String idStaffInput = console.nextLine();
boolean check = m_staff.setIdStaff(idStaffInput);
if (check) {
break;
}
}

// 5.2 Manager Name Input
System.out.println("Please enter the manager's name: ");
while (true) {
String nameStaffInput = console.nextLine();
boolean check = m_staff.setNameStaff(nameStaffInput);
if (check) {
break;
}
}

// 5.3 Manager Age Input
System.out.println("Please enter the manager's age: ");
while (true) {
int ageStaffInput = getInt();
boolean check = m_staff.setAgeStaff(ageStaffInput);
if (check) {
break;
}
}

// 5.4 Salary Weight Input
System.out.println("Please enter his/her salary weight: ");
while (true) {
int salaryWeightInput = getInt();
boolean check = m_staff.setSalaryWeight(salaryWeightInput);
if (check) {
break;
}
}

// 5.5 Starting Date Input
System.out.println("Please enter the manager's starting date: ");
String dateStartInput = console.nextLine();
while (!m_staff.setDateStart(dateStartInput)) {
System.err.println("Please enter as the Date format as dd/MM/yyyy");
dateStartInput = console.nextLine();
}

// 5.6 Department Choosing
System.out.println("List of Department: ");
System.out.println("Press 1 for Business Department.");
System.out.println("Press 2 for Project Department.");
System.out.println("Press 3 for Technical Department.");
System.out.println("Please choose the employee's department from one of three choices above: ");
// Choose 1 in 3 Department then that Department Staff quantity increases by 1
while (true) {
int departmentInput = getInt();
if (departmentInput == 1) { // User choose 1
m_staff.setDepartment(listDepartment.get(0));
// Set the number Staff in Business Department increased by 1 in class Department
listDepartment.get(0).setNumberStaffDepartment(listDepartment.get(0).getNumberStaffDepartment() + 1);
break;
} else if (departmentInput == 2) { // User choose 2
m_staff.setDepartment(listDepartment.get(1));
listDepartment.get(1).setNumberStaffDepartment(listDepartment.get(1).getNumberStaffDepartment() + 1);
break;
} else if (departmentInput == 3) { // User choose 3
m_staff.setDepartment(listDepartment.get(2));
listDepartment.get(2).setNumberStaffDepartment(listDepartment.get(2).getNumberStaffDepartment() + 1);
break;
} else {
System.err.println("Please enter only number 1, 2, or 3!");
}
}

// 5.7 Day Off Quantity Input
System.out.println("Please enter the manager's number of day off: ");
while (true) {
int dayOffQuantityInput = getInt();
boolean check = m_staff.setDayOffQuantity(dayOffQuantityInput);
if (check) {
break;
}
}

// 5.8 Manager Title Input
System.out.println("Please enter the manager's title: ");
while (true) {
String titleInput = console.nextLine();
// Downcasting the titleInput variable from m_staff variable belonging to class Staff down to become a variable in class Manager so the class Manager can use this variable for the following method
boolean check = ((Manager) m_staff).setTitle(titleInput);
if (check) {
break;
}
}

// Finishing filling all the properties of an object m_staff and save to the listStaff ArrayList with the next index
listStaff.add(m_staff);
}

// Feature 6 - Searching a staff's information based on a name
public static void searchNameStaff() {
breakLine();
System.out.println("SEARCH THE STAFF'S INFORMATION BASED ON THE STAFF'S NAME");
System.out.println("Please enter the Staff's Name you want to look up: ");
String nameStaffSearch = console.nextLine();
int count = 0; // for moving to the next index in the listStaff arraylist
// For Loop to Scan through all the elements inside the listStaff arraylist
for (Staff staff : listStaff) {
if (staff.getNameStaff().equalsIgnoreCase(nameStaffSearch)) { // If a name in listStaff has the same String with the user input query
System.out.println("Yes, there is a staff having this name, whose information is displayed below: ");
staff.displayInformation();
count++;
}
}
// After scanning through the listStaff arraylist but cannot find the matching name, so the count does not increase
if (count == 0) {
System.out.println("There is no staff having this id of "" + nameStaffSearch + "".");
}
}

// Feature 7 - Searching a staff's information based on an id
public static void searchIdStaff() {
breakLine();
System.out.println("SEARCH THE STAFF'S INFORMATION BASED ON THE STAFF'S ID");
System.out.println("Please enter the Staff's Id you want to look up: ");
String idStaffSearch = console.nextLine(); // Get the user input for search query
int count = 0; // for moving to the next index in the listStaff arraylist
// For Loop to Scan through all the elements inside the listStaff arraylist
for (Staff staff : listStaff) {
if (staff.getIdStaff().equalsIgnoreCase(idStaffSearch)) {
System.out.println("Yes, there is a staff having this id, whose information is displayed below: ");
staff.displayInformation();
count++;
}
}
// After scanning through the listStaff arraylist but cannot find the matching id, so the count does not increase
if (count == 0) {
System.out.println("There is no staff having this id of "" + idStaffSearch + "".");
}
}

// Feature 8 - Showing all the staff's salary
public static void displayAllSalary() {
breakLine();
System.out.println("ALL THE STAFF'S SALARY INFORMATION:");
for (int i = 0; i < listStaff.size(); i++) {
int salary = 0;
System.out.print(i + 1 + ". ");
System.out.print(listStaff.get(i).getNameStaff()); // Display the staff's name
System.out.print("; Salary: ");
// Downcasting the instance listStaff.get(i) belongs to class Staff down to become an object of Employee class
if (listStaff.get(i) instanceof Employee) {
Employee e = (Employee) listStaff.get(i);
salary = e.calculateSalary();
}
// Downcasting the instance listStaff.get(i) belongs to class Staff down to become an object of Manager class
if (listStaff.get(i) instanceof Manager) {
Manager m = (Manager) listStaff.get(i);
salary = m.calculateSalary();
}
System.out.print(salary); // Display the Salary
System.out.println(); // Enter another line for the next index information
}
}

// Feature 9 - Sorting the staff's salary in ascending order
public static void sortSalaryAscending() {
Collections.sort(listStaff, new Comparator<Staff>() { // Loop through the listStaff arrayList
@Override
public int compare(Staff o1, Staff o2) { // Create 2 objects in the Staff class to consecutively go through each index
// Downcast o1 and o2 to access the calculateSalary() method in 2 Employee and Manager classes to return a number to compare
int salary1 = 0;
// TODO Staff class already implements ICalculator so that Don't need the If parts here
//salary1 = o1.calculateSalary();
if(o1 instanceof Employee){ // if o1 is an instance created by the class Employee
Employee e = (Employee) o1;
salary1 = e.calculateSalary();
} else { // if o1 instanceof Manager
Manager m = (Manager) o1;
salary1 = m.calculateSalary();
}
int salary2 = 0;
if(o2 instanceof Employee){ // if o2 is an instance created by the class Employee
Employee e = (Employee) o2;
salary2 = e.calculateSalary();
} else { // if o2 instanceof Manager
Manager m = (Manager) o2;
salary2 = m.calculateSalary();
}
// Compare 2 Salaries value
if (salary1 >= salary2) { // if o1 > o2
return 1; // switch the index order, so o1 will be placed after o2
} else { // if o1 < o2
return -1; // do not switch the index order, so o1 will be placed before o2
}
}
});
// Display the new Ascending order of listStaff
breakLine();
System.out.println("ALL THE STAFF'S SALARY BASED ON SALARY IN ASCENDING ORDER");
for (int i = 0; i < listStaff.size(); i++) {
int salary = 0;
System.out.print(i + 1 + ". ");
System.out.print(listStaff.get(i).getNameStaff()); // Display the Staff's Name
System.out.print("; Salary: ");
// Display the Salary of this Staff
// Downcasting the instance listStaff.get(i) belongs to class Staff down to become an object of Employee class
if (listStaff.get(i) instanceof Employee) {
Employee e = (Employee) listStaff.get(i);
salary =e.calculateSalary();
}
// Downcasting the instance listStaff.get(i) belongs to class Staff down to become an object of Manager class
if (listStaff.get(i) instanceof Manager) {
Manager m = (Manager) listStaff.get(i);
salary = m.calculateSalary();
}
System.out.print(salary); // Display the Staff's Salary
System.out.println(); // Enter another line for another index in the list
}
}

// Feature 10 - Sorting the staff's salary in descending order.
public static void sortSalaryDescending() {
Collections.sort(listStaff, new Comparator<Staff>() {
@Override
public int compare(Staff o1, Staff o2) {
// Downcast o1 and o2 to access the calculateSalary() method in 2 Employee and Manager classes to return a number to compare
int salary1 = 0;
if(o1 instanceof Employee){ // if o1 is an instance created by the class Employee
Employee e = (Employee) o1;
salary1 = e.calculateSalary();
} else { // if o1 instanceof Manager
Manager m = (Manager) o1;
salary1 = m.calculateSalary();
}
int salary2 = 0;
if(o2 instanceof Employee){ // if o2 is an instance created by the class Employee
Employee e = (Employee) o2;
salary2 = e.calculateSalary();
} else { // if o2 instanceof Manager
Manager m = (Manager) o2;
salary2 = m.calculateSalary();
}
// Compare 2 Salaries value
return salary1 >= salary2? -1: 1; // return condition ? a : b; == if( condition ) {return a;} else {return b;}
}
});
// Display the new Descending order of listStaff
breakLine();
System.out.println("ALL THE STAFF'S SALARY BASED ON SALARY IN DESCENDING ORDER");
for (int i = 0; i < listStaff.size(); i++) {
int salary = 0;
System.out.print(i + 1 + ". ");
System.out.print(listStaff.get(i).getNameStaff()); // Display the Staff's Name
System.out.print("; Salary: ");
// Display the Salary of this Staff
// Downcasting the instance listStaff.get(i) belongs to class Staff down to become an object of Employee class
if (listStaff.get(i) instanceof Employee) {
Employee e = (Employee) listStaff.get(i);
salary =e.calculateSalary();
}
// Downcasting the instance listStaff.get(i) belongs to class Staff down to become an object of Manager class
if (listStaff.get(i) instanceof Manager) {
Manager m = (Manager) listStaff.get(i);
salary = m.calculateSalary();
}
System.out.print(salary); // Display the Staff's Salary
System.out.println(); // Enter another line for another index in the list
}
}

// Method to check the correct number input
// TODO Check if it's a negative number
public static int getInt() {
int userInput = 0; // grant as 0 to avoid the uninitialized error
do {
System.out.println("Please enter a number as an Integer!");
if (console.hasNextInt()) {
userInput = console.nextInt();
console.nextLine(); // Clear Scanner
break;
} else {
console.nextLine(); // Clear Scanner
System.err.println("Wrong input!");
}
} while (true);
return userInput;
}

// Method to create a new paragraph
public static void breakLine() {
System.out.println();
System.out.println();
}
}