Comparable

Imagine you write a simple class called Cake:

public class Cake {
    private String name;
    private String description;
    private int weight;

    // constructor

    // getters and setters
}

You want to define the ordering by name. Which of the examples below is correct?

1. public class Cake {
       private String name;
       private String description;
       private int weight;
   
       // constructor
   
       // getters and setters
   
       @Override
       public int compareTo(Cake otherCake) {
           return getName().compareTo(otherCake.getName());
       }
   }
   

2. public class Cake implements Comparable<Cake> {
       private String name;
       private String description;
       private int weight;
   
       // constructor
   
       // getters and setters
   
       @Override
       public int compareTo(Cake otherCake) {
           return getName().compareTo(otherCake.getName());
       }
   }
   

3. public class Cake implements Comparable<Cake> {
       private String name;
       private String description;
       private int weight;
   
       // constructor
   
       // getters and setters
   
       @Override
       public int compareTo(Cake cake, Cake otherCake) {
           return cake.getName().compareTo(otherCake.getName());
       }
   }
   

4. public class Cake implements Comparable<Cake> {
       private String name;
       private String description;
       private int weight;
   
       // constructor
   
       // getters and setters
   
       @Override
       public int compareTo(Cake otherCake) {
           return otherCake.getName().compareTo(getName());
       }
   }