printing data from objects

[vladimir mujakovic]

hi i been working on this project all day and am hitting a wall, I am supposed to write a program that accepts data from the user and prints it to the console. it involves using inheritance. i have for the most part figured out how to write the classes now i am stuck with my main method. i dont know how to store the data in the class object this is my code so far please help im stuck

import java.util.Scanner;

public class CH08PR82App {

    public static void main(String[] args) {

        System.out.print("Welcome to the Person Tester Application");
        System.out.println();

        Scanner sc = new Scanner(System.in);

        String choice = "y";
        while (choice.equalsIgnoreCase("y")) {

            //prompt user to enter customer or employee
            System.out.print("Create customer or employee (c/e): ");
            String userType = sc.nextLine();

            if (userType.equalsIgnoreCase("c")) {
            
            String fName = Validator.getStringInput(sc, "Enter first name: ");
            String lastName = Validator.getStringInput(sc, "Enter last name: ");
            String email = Validator.getStringInput(sc, "Enter email address: ");
            String custNumber = Validator.getStringInput(sc, "Customer number: ");
            
            
            } else if (userType.equalsIgnoreCase("e")) {
                
            String firstName = Validator.getStringInput(sc, "Enter first name: ");
            String lastName = Validator.getStringInput(sc, "Enter last name: ");
            String email = Validator.getStringInput(sc, "Enter email address: ");
            String socialSecNumber = Validator.getStringInput(sc, "Social security number: ");
            
            
            }
            choice = Validator.getStringContinue(sc, "Continue? (y/n): ");
        }
    }
    public static void print(Person person) {
    System.out.println(person.getDisplayText());
}
}
abstract class Person {

    private String firstName;
    private String lastName;
    private String eMail;

    public Person() {
        firstName = "";
        lastName = "";
        eMail = "";
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public String geteMail() {
        return eMail;
    }

    public void seteMail(String eMail) {
        this.eMail = eMail;
    }

    @Override
    public String toString() {
        return "Name: " + firstName + lastName + "\n"
                + "E-mail: " + eMail;
    }
abstract String getDisplayText();

}

class Customer extends Person {

    private String customerNumber;

    public Customer() {
        super();
        customerNumber = "";
    }

    public void setcustomerNumber(String customerNumber) {
        this.customerNumber = customerNumber;
    }

    public String getcustomerNumber() {
        return customerNumber;
    }

    @Override
    public String getDisplayText() {
        return super.toString() + "\n"
                + "Customer number: " + customerNumber + "\n";
    }
   

}

class Employee extends Person {

    private String socNumber;

    public Employee() {
        super.toString();
        socNumber = "";
    }

    public void setsocNumber(String socNumber) {
        this.socNumber = socNumber;
    }

    public String getsocNumber() {
        return socNumber;
    }
    @Override
    public String getDisplayText() {
        return super.toString()
                + "Social Security number:      " + socNumber + "\n";
    }
    
}


class Validator {

    public static String getStringContinue(Scanner sc, String prompt) {
        boolean isValid = false;
        String s = "";
        while (isValid == false) {
            System.out.print(prompt);
            if (sc.hasNext("y")) {
                s = sc.nextLine(); // read entire line
                isValid = true;
            } else if (sc.hasNext("n")) {
                s = sc.nextLine();
                isValid = true;
            } else {
                s = sc.nextLine();
                isValid = false;
                System.out.println("Error! Invalid string value. Try again.");
            }
        }
        return s;
    }

    public static String getStringInput(Scanner sc, String prompt) {
        boolean isValid = false;
        String s = "";
        while (isValid == false) {
            System.out.print(prompt);
            if (sc.hasNext()) {
                s = sc.nextLine(); // read entire line
                isValid = true;
            } else {
                System.out.println("Error! Invalid string value. Try again.");
            }
        }
        return s;
    }

    

   

i attempted to write as follows

String fName = Validator.getStringInput(sc, "Enter first name: ");
            String lastName = Validator.getStringInput(sc, "Enter last name: ");
            String email = Validator.getStringInput(sc, "Enter email address: ");
            String custNumber = Validator.getStringInput(sc, "Customer number: ");
            Person c = new Customer(fName, lastName, email, custNUmber)

but i get redlines on netbeans, i dont understand. the object is to print the user data to the console.

[K. Tsang]

Did you print out the "s" once it's read in the Validator.getStringInput() method?

And what does Netbeans say about the red lines?

[vladimir mujakovic]

im sorry i must not be clear on what im asking.

let me rephrase,

im asking about how to print data thats been entered by the user, more importantly im trying to pass the user entered values to an object of the person class. and then print that.



so im trying to pass the user entered value to an object.

if i store first name like so

String firstName = sc.next();

why cant i simply pass this value to an object by typing -->

Person c = new Customer(firstName);
keep in mind im using inheritance and overriding the toString method, not sure if that makes a difference
im trying to create Person c = new Customer(variable value);
so that c equals the value of the user input so i can then print it. but netbeans wont allow me to do it.

[K. Tsang]

vladimir mujakovic wrote:String firstName = sc.next();

why cant i simply pass this value to an object by typing -->

Person c = new Customer(firstName);

Ah does your Customer have a constructor like "Customer(String)?

Even Customer is a subclass of Person, you need a constructor for each class if you are NOT using the default empty constructor.

[vladimir mujakovic]

how would that look?

my code is above it has all the classes i have so far. i am using constructors with no arguments at the moment. what should they be?

[K. Tsang]

There are 2 ways to achieve what you want to do. And your current approach (using empty constructor in those Person etc classes) does not match up with using parameterized constructors in your main method.

//approach 1
public class Customer {
  private String name;
  // empty constructor
  public Customer() {
    name = "";
  }
  public String getName() {
    return name;
  }
  public void setName(String name) {
    this.name = name;
  }
}

public static void main(String[] args) {
  // once you got the scanner stuff
  String name = ...
  Customer cust = new Customer();
  cust.setName(name);
}

//approach 2
public class Customer {
  private String name;

  //empty constructor
  public Customer() {} // do nothing, variable name remains null

  // parameterized constructor
  public Customer(String name) {
    this.name = name; 
  }
  public String getName() {
    return name;
  }
  public void setName(String name) {
    this.name = name;
  }
}

public static void main(String[] args) {
  // once you got the scanner stuff
  String name = ...
  Customer cust = new Customer(name);
}

I hope you see the difference. And this is what Netbeans is telling you "there are no parameterized constructors"