Treehouse online IDE keeps complaining about getter for 'id' is missing, but I am following the bean naming conventions?

package com.teamtreehouse.contactmgr.model;

public class Contact {
  public int id;
  public String firstName;
  public String lastName;
  public String email;

  public int getId() {
    return this.id;
  }

  public void setId(int id) {
    this.id = id;
  }

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

  public String getFirstName() {
    return this.firstName;
  }

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

  public String getLastName() {
    return this.lastName;
  }

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

  public String getEmail() {
    return this.email;
  }

}