Question

Part I: (The Myate class) Design a class named MyDate. The class contains: • The data fields year, month, and day that represent a date. Month is 0-based, i.e., 0 is for January. • A no-arg constructor that creates a MyDate object for the current date. • A constructor that constructs a MyDate object with a specified elapsed time since midnight, January 1, 1970, in milliseconds. • A constructor hat constructs a MyDate object with the specified year, month, and day. • Three getter methods for the data fields, year, month, and day, respectively. • A method named setDate(long elapsedTime) that sets a enw date for the object using the elapsed time. • Write a test program that creates two MyDate objects (using new MyDate() and new MyDate(34355555133101L) and displays their year, month, and day. (Hint: The first two constructors will extract the year, month, and day from the elapsed time. For example, if the elapsed time is 561555550000 milliseconds, the year is 1987, the month is 9, and day is 18. You may use the GregorianCalandear class. Java API has the GregorianCalendar class in the java.tuil package, which you can use to obtain the year, month, and day of date. The no-arg constructor constructs an instance for the current date, and the mentod get(GregorianCalendar.YEAR), get(GregorianCalendar.MONTH), and get(GregorianCalendar.DAY_OF_MONTH) return the year, month, and day.)

Part II: (The Person, Student, Employee, Faculty, and Staff classes) Design a class named Person and its two subclasses named Student and Employee. Make Faculty and Staff subclasses of Employee. A person has a name, address, phone number, and email address. A student has a class status (freshman, sophomore, junior, or senior). Define the status as a constant. An employee has an office, salary, and date hired. Use the MyDate class defined in Part I to create an object for date hired. A faculty member has office hours and a rank. A staff member has a title. Override the toString metod in each class to display the class name and the person’s name. Part III: Write a test program that creates a Person, Student, Employee, Faculty, and Staff, and invokes their toString() methods.

Answer 1

Part - 1 : :

import java.util.*;

class Date {
public static void main(String[] args) {
MyDate d1 = new MyDate();
       d1.display();
       MyDate d2 = new MyDate(34355555133101L);
       d2.display();
       MyDate d3 = new MyDate(561555550000L);
       d3.display();
}
  
  
}

class MyDate{
   Calendar c = Calendar.getInstance();
   private int year, month, day;
  
   public MyDate(){
       this(System.currentTimeMillis());
   }
  
   public MyDate(long millis){
       setDate(millis);
   }
  
   public MyDate(int year, int month, int day){
       this.year = year;
       this.month = month;
       this.day = day;
   }
  
   public int getYear(){
       return year;
   }
  
   public int getMonth(){
       return month;
   }
  
   public int getDay(){
       return day;
   }
  
   public void setDate(long millis){
       c.setTimeInMillis(millis);
       year = c.get(Calendar.YEAR);
       month = c.get(Calendar.MONTH);
       day = c.get(Calendar.DAY_OF_MONTH);
   }
  
   public void display(){
   System.out.printf("%d/%d/%d (mm/dd/yyyy)\n", month, day, year);
}
}

Part - 2 ::

Person.java

public class Person {

protected String name;
protected String address;
protected String phoneNumber;
protected String email;

public Person(String name) {
this.name = name;
}

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

public String getAddress() {
return address;
}

public void setAddress(String address) {
this.address = address;
}

public String getPhoneNumber() {
return phoneNumber;
}

public void setPhoneNumber(String phoneNumber) {
this.phoneNumber = phoneNumber;
}

public String getEmail() {
return email;
}

public void setEmail(String email) {
this.email = email;
}

@Override
public String toString() {
return "Name: " + getName() + " Class: " + this.getClass().getName();
}
}

Student.java

public class Student extends Person {

public static final String FRESHMAN = "Freshman";
public static final String SOPHOMORE = "Sophomore";
public static final String JUNIOR = "Junior";
public static final String SENIOR = "Senior";

protected String status;

public Student(String name) {
super(name);
}

public Student(String name, String status) {
super(name);
this.status = status;
}

@Override
public String toString() {
return "Name: " + getName() + " Class: " + this.getClass().getName();
}
}

Employee.java

public class Employee extends Person {

protected double salary;
protected String office;
protected MyDate dateHired;

public Employee(String name) {
this(name, 0, "none", new MyDate());
}

public Employee(String name, double salary, String office, MyDate dateHired) {
super(name);
this.salary = salary;
this.office = office;
this.dateHired = dateHired;
}

public double getSalary() {
return salary;
}

public void setSalary(double salary) {
this.salary = salary;
}

public String getOffice() {
return office;
}

public void setOffice(String office) {
this.office = office;
}

public MyDate getDateHired() {
return dateHired;
}

public void setDateHired(MyDate dateHired) {
this.dateHired = dateHired;
}

@Override
public String toString() {
return "Name: " + getName() + " Class: " + this.getClass().getName();
}
}

Faculty.java

public class Faculty extends Employee {

public static String LECTURER = "Lecturer";
public static String ASSISTANT_PROFESSOR = "Assistant Professor";
public static String ASSOCIATE_PROFESSOR = "Associate Professor";
public static String PROFESSOR = "Professor";

protected String officeHours;
protected String rank;

public Faculty(String name) {
this(name, "9-5PM", "Employee");
}

public Faculty(String name, String officeHours, String rank) {
super(name);
this.officeHours = officeHours;
this.rank = rank;
}

public String getOfficeHours() {
return officeHours;
}

public void setOfficeHours(String officeHours) {
this.officeHours = officeHours;
}

public String getRank() {
return rank;
}

public void setRank(String rank) {
this.rank = rank;
}

@Override
public String toString() {
return "Name: " + getName() + " Class: " + this.getClass().getName();
}
}

Staff.java

public class Staff extends Employee {

protected String title;

public Staff(String name) {
this(name, "none");

}

public Staff(String name, String title) {
super(name);
this.title = title;
}

public String getTitle() {
return title;
}

public void setTitle(String title) {
this.title = title;
}

@Override
public String toString() {
return "Name: " + getName() + " Class: " + this.getClass().getName();
}
}

Main.java

public class Main {

public static void main(String[] args) {

Person person = new Person("Test1");
Student student = new Student("StuTest1");
Employee employee = new Employee("TestEmp1");
Faculty faculty = new Faculty("TestFac");
Staff staff = new Staff("TestStaff");

System.out.println(person.toString());
System.out.println(student.toString());
System.out.println(employee.toString());
System.out.println(faculty.toString());
System.out.println(staff.toString());

}

}

Output ::

Please do comment if you have any doubts ...