А вот код на Java:

public class Customer {

   private String name;

   private String email;

   private String company;

   public Customer(String name) {

       this(name, "", "");

   }

   public Customer(String name, String email) {

       this(name, email, "");

   }

   public Customer(String name, String email, String company) {

       this.name = name;

       this.email = email;

       this.company = company;

   }

   public String getName() {

       return name;

   }

   public void setName(String name) {

       this.name = name;

   }

   public String getEmail() {

       return email;

   }

   public void setEmail(String email) {

       this.email = email;

   }

   public String getCompany() {

       return company;

   }

   public void setCompany(String company) {

       this.company = company;

   }

   @Override

   public boolean equals(Object o) {

       if (this == o) return true;

       if (o == null || getClass() != o.getClass()) return false;

       Customer customer = (Customer) o;

       if (name != null ? !name.equals(customer.name) : customer.name != null) return false;

       if (email != null ? !email.equals(customer.email) : customer.email != null) return false;

       return company != null ? company.equals(customer.company) : customer.company == null;

   }

   @Override

   public int hashCode() {

       int result = name != null ? name.hashCode() : 0;

       result = 31 * result + (email != null ? email.hashCode() : 0);

       result = 31 * result + (company != null ? company.hashCode() : 0);

       return result;

   }

   @Override

   public String toString() {

       return "Customer{" +

               "name='" + name + '\'' +

               ", email='" + email + '\'' +

               ", company='" + company + '\'' +

               '}';

   }

}