Q3: Create a class called Employee that includes three instance variables—a first name (typeString), a last name (type String) and a monthly salary (double). Provide a constructor that initializesthe three instance variables. Provide a set and a get method for each instance variable. If the monthly salary is not positive, do not set its value. {Do not write a full program, only a class}

Follows are the code to the given question:

public class Employee //defining a class Employee

{

String first_name,last_name;

Double monthly_salary;

Employee(String first_name,String last_name,Double monthly_salary)

{

   this first_name=f_name// initialize value in first_name

   this last_name = l_name; // initialize value in the last_name

    this monthly_salary = m_salary; // initialize value in the monthly_salary

if (monthly_salary < 0.0)//use if to check monthly_salary is positive

           monthly_salary = 0.0;//set value 0

}

void setfirst_name (String f_name)//defining set method to store first_name

{

first_name = f_name;//holding the value of first_name

}  

public String getfirst_name ()//defining get method to return first_name

{

return first_name;//return first_name

}  

public void setlast_name (String l_name)//defining set method to store last_name

{

last_name = l_name;// holding the value of the last_name

}

public String getlast_name ()//defining get method to return last_name

{

return last_name;//return last_name

}  

public void setmonthly_salary(double m_salary)//defining set method to store monthly_salary

{

monthly_salary = m_salary;// holding the value of the monthly_salary

}

public double getmonthly_salary ()//defining get method to return monthly_salary

{

return monthly_salary;//return monthly_salary  

}

}

Explanation:

In this code, a class "Employee" is declared that defines two string variables  "first_name,last_name", and one double variable "monthly_salary". In the next step, a parameterized constructor is defined that stores the value into the variable, and use if block to check "monthly_salary" is a positive. It also uses the getter and setter method to hold and return its value.