Contact

public class Contact implements Comparable<Contact> {

    private String lastName;
    private String firstName;
    private String email;


    public Contact(String lastName, String firstName, String email) {

        this.lastName = lastName;
        this.firstName = firstName;
        this.email = email;
    }


    public String getLastName() {
        return lastName;
    }

    public String getFirstName() {
        return firstName;
    }

    public String getEmail() {
        return email;
    }

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


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

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

    // Forces the natural ordering to be based on last names.
    // If last names are the same, ignoring cases, then sort based on first name.
    @Override
    public int compareTo(Contact that) {
        if (this.getLastName().compareToIgnoreCase(that.getLastName()) == 0) {
            return this.getFirstName().compareToIgnoreCase(that.getFirstName());
        } else {
            return this.getLastName().compareToIgnoreCase(that.getLastName());
        }
    }

    @Override
    public String toString() {
        return "First Name: " + firstName + "\n" +
                "Last Name: " + this.lastName + "\n" +
                "Email: " + this.getEmail() + "\n"; // or getEmail()
    }

}