Exercise 4

Create a Java class Person with the following attributes:

name (a string)

age (an integer)

gender (a string)

The class should have the following methods:

setName(String name): This method should set the name of the person.

setAge(int age): This method should set the age of the person.

setGender(String gender): This method should set the gender of the person.

getName(): This method should return the name of the person.

getAge(): This method should return the age of the person.

getGender(): This method should return the gender of the person.

Create a Java class Employee that extends the Person class and has the following additional attributes:

salary (a double)

jobTitle (a string)

The class should have the following additional methods:

setSalary(double salary): This method should set the salary of the employee.

setJobTitle(String jobTitle): This method should set the jobTitle of the employee.

getSalary(): This method should return the salary of the employee.

getJobTitle(): This method should return the jobTitle of the employee.

You should also write a Main class that creates an Employee object, sets its attributes, and demonstrates the use of each of the methods.

Create a Java class Student that has the following attributes:

name (a string)

age (an integer)

grades (an array of doubles)

The class should have the following methods:

getName(): This method should return the student's name.

getAge(): This method should return the student's age.

getGrades(): This method should return the student's grades.

getAverage(): This method should calculate and return the student's average grade.

You should also write a Main class that creates an array of Student objects, populates it with data, and then calculates and prints out the average grade for each student.

Create a Java class Rectangle that has the following attributes:

width (a double)

height (a double)

The class should have the following methods:

getArea(): This method should return the area of the rectangle, which is calculated as width * height.

getPerimeter(): This method should return the perimeter of the rectangle, which is calculated as 2 * (width + height).

You should also write a Main class that creates two Rectangle objects, sets their width and height, and demonstrates the use of each of the methods.