Question

Java Program - Inheritance/Polymophism

TelecomOperator

• PrepaidConnection (plans,rates)
• PostPaidConnection(plans,rates,duration)

Trainer

• TrainerName
• TrainerId
• Department

mathTrainer extends Trainer

• Subject
• courseDuration

EnglishTrainer

• subject
• courseDuration

Use runtime Polymorphism and make all the variables as private

FinanceClass

• CustomerInfo
  • custname
  • custid
  • address
  • age
  • salary

     

• HomeLoan
  • Criteria for home loan
  • Customer should have min sal=30000
  • Age of customer should be greater than 18

• CarLoan
  • Criteria for car loan
  • Customer should have min sal=15000
  • Age of customer should be greater than 18

• PersonalLoan
  • Criteria for personal loan
  • Customer should have min sal=10000
  • Age of customer should be greater than 18

Answer 1

Program:

/*********************** File name: Trainer.java ***********************/
public class Trainer
{
private String trainerName;
private int trainerId;
private String department;

public Trainer()
{  
  trainerName = "";
  trainerId = 0;
  department = "";
}

public Trainer(String trainerName, int trainerId, String department)
{  
  this.trainerName = trainerName;
  this.trainerId = trainerId;
  this.department = department;
}

public String gettrainerName()
{
  return trainerName;
}

public void settrainerName(String trainerName)
{
  this.trainerName = trainerName;
}

public int gettrainerId()
{
  return trainerId;
}

public void settrainerId(int trainerId)
{
  this.trainerId = trainerId;
}

public String getdepartment()
{
  return department;
}

public void setdepartment(String department)
{
  this.department = department;
}

@Override
public String toString()
{
  return "Trainer [trainerName=" + trainerName + ", trainerId=" + trainerId + ", department=" + department + "]";
}

}

/*********************** File name: EnglishTrainer.java ***********************/
public class EnglishTrainer extends Trainer
{
private String subject;  
private String courseDuration;

public EnglishTrainer()
{
  super();
  this.subject = "";
  this.courseDuration = "";
}
public EnglishTrainer(String trainerName,int trainerId, String department, String subject, String courseDuration)
{
  super(trainerName, trainerId, department);
  this.subject = subject;
  this.courseDuration = courseDuration;
}

public String getSubject()
{
  return subject;
}
public void setSubject(String subject)
{
  this.subject = subject;
}
public String getCourseDuration()
{
  return courseDuration;
}
public void setCourseDuration(String courseDuration)
{
  this.courseDuration = courseDuration;
}

@Override
public String toString()
{
  return "EnglishTrainer [subject=" + subject + ", courseDuration=" + courseDuration + ", toString()="
    + super.toString() + "]";
}

}
/*********************** File name: MathTrainer.java ***********************/
public class MathTrainer extends Trainer
{
private String subject;
private String courseDuration;

public MathTrainer()
{
  super();
  subject = "";
  this.courseDuration = "";
}

public MathTrainer(String trainerName,int trainerId, String department,String subject, String courseDuration)
{
  super(trainerName,trainerId,department);
  this.subject = subject;
  this.courseDuration = courseDuration;
}

public String getsubject()
{
  return subject;
}

public void setsubject(String subject)
{
  this.subject = subject;
}

public String getCourseDuration()
{
  return courseDuration;
}

public void setCourseDuration(String courseDuration)
{
  this.courseDuration = courseDuration;
}

@Override
public String toString()
{
  return "mathTrainer [subject=" + subject + ", courseDuration=" + courseDuration + ", toString()="
    + super.toString() + "]";
}
}

/*********************** File name: TrainerDemo.java ***********************/
public class TrainerDemo
{

public static void main(String[] args)
{
  // Create an object named mt for the trainer class
  Trainer mt = new MathTrainer("John Carlos",10101,"Training","Mathematics","45 days");
  Trainer et = new EnglishTrainer("Michal Richard",10102,"Training","English","90 days");
  
  // Here the objects mt and et are related to
  // the same class named Trainer. But each object
  // performs and behaves differently.
  System.out.println(mt.toString());
  System.out.println(et.toString());

}
}

Sample output screenshot:

$9k=$

Program 2: Loan using Polymorphism

Program:

/********************** File name: CustomerInfo.java **********************/
public class CustomerInfo
{
private String custname;
private int custid;
private String address;
private int age;
private double salary;

public CustomerInfo()
{
  this.custname = "";
  this.custid = 0;
  this.address = "";
  this.age = 0;
  this.salary = 0.00;
}

public CustomerInfo(String custname, int custid, String address, int age, double salary)
{
  super();
  this.custname = custname;
  this.custid = custid;
  this.address = address;
  this.age = age;
  this.salary = salary;
}

public String getCustname()
{
  return custname;
}

public void setCustname(String custname)
{
  this.custname = custname;
}

public int getCustid()
{
  return custid;
}

public void setCustid(int custid)
{
  this.custid = custid;
}

public String getAddress()
{
  return address;
}

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

public int getAge()
{
  return age;
}

public void setAge(int age)
{
  this.age = age;
}

public double getSalary()
{
  return salary;
}

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

@Override
public String toString()
{
  return "CustomerInfo [custname=" + custname + ", custid=" + custid + ", address=" + address + ", age=" + age
    + ", salary=" + salary + "]";
}

}

/********************** File name: HomeLoan.java **********************/
public class HomeLoan extends CustomerInfo
{
private String loanType;
private String eligible;

public HomeLoan()
{
  super();
  this.loanType = "";
  this.eligible = "";
}

public HomeLoan(String custname, int custid, String address, int age, double salary, String loanType)
{
  super(custname, custid, address, age, salary);
  this.loanType = loanType;
  
  if (salary>=30000 && age >18)
  {
   this.eligible = "Elegible";
  }
  else
  {
   this.eligible = "Not Elegible";
  }  
}

@Override
public String toString()
{
  return "HomeLoan [loanType=" + loanType + ", eligible=" + eligible + ", toString()=" + super.toString() + "]";
}

}

/********************** File name: CarLoan.java **********************/
public class CarLoan extends CustomerInfo
{
private String loanType;
private String eligible;

public CarLoan()
{
  super();
  this.loanType = "";
  this.eligible = "";
}

public CarLoan(String custname, int custid, String address, int age, double salary, String loanType)
{
  super(custname, custid, address, age, salary);
  this.loanType = loanType;
  
  if (salary>=15000 && age >18)
  {
   this.eligible = "Elegible";
  }
  else
  {
   this.eligible = "Not Elegible";
  }  
}

@Override
public String toString()
{
  return "CarLoan [loanType=" + loanType + ", eligible=" + eligible + ", toString()=" + super.toString() + "]";
}

}

/********************** File name: PersonalLoan.java **********************/
public class PersonalLoan extends CustomerInfo
{
private String loanType;
private String eligible;

public PersonalLoan()
{
  super();
  this.loanType = "";
  this.eligible = "";
}

public PersonalLoan(String custname, int custid, String address, int age, double salary, String loanType)
{
  super(custname, custid, address, age, salary);
  this.loanType = loanType;
  
  if (salary<=10000 && age >18)
  {
   this.eligible = "Elegible";
  }
  else
  {
   this.eligible = "Not Elegible";
  }  
}

@Override
public String toString()
{
  return "PersonalLoan [loanType=" + loanType + ", eligible=" + eligible + ", toString()=" + super.toString() + "]";
}

}

/********************** File name: LoanDemo.java **********************/
public class LoanDemo
{

public static void main(String[] args)
{
  CustomerInfo cust1= new HomeLoan( "Michal Richard", 1011, "Flat: 10, calfonia, USA", 33, 55000.00, "Home Loan");
  CustomerInfo cust2= new CarLoan( "John Carlos", 1012, "Flat: 5, calfonia, USA", 17, 0.000, "Car Loan");
  CustomerInfo cust3= new PersonalLoan( "Gabrella Johnson", 1013, "Flat: 32, calfonia, USA", 24, 12000.00, "Personal Loan");
  
  System.out.println(cust1.toString());
  System.out.println(cust2.toString());
  System.out.println(cust3.toString());
}

}

Sample output screenshot: