接口或类中的Java枚举放置

我试图理解Java中的枚举,但目前找不到解释我问的问题的帖子.

我有一个Person界面和一个PersonEO类.Person接口的两种方法是setGender和getGender.我想把性别作为一个枚举.

我是否在界面中创建枚举并将其转移到课程中,或者在课堂上创建枚举？

这是我一直在尝试的但是无法让enum正确地传递给类,并且不能真正理解它将如何流经程序.

public interface Person{
    public enum gender{
    Female,
    Male,
    Unknown;

       private String gender;

       public String getGender(){
       }

       void setGender(){  
       }
}


------------------------------------------------------


public class PersonEO implements Person {
   //Both override methods are not seen as methods from the interface

   @Override
   public String getGender() {
       return gender;
   }

   @Override
   public void setGender() {
       //Not sure how to set the gender from the enum
       this.gender = gender;
   }
}

请举例说明.

枚举,接口和类都是单独的类型,通常应该在单独的文件中.以下是一些示例定义:

enum Gender {
    MALE, FEMALE, UNKNOWN;
}

interface Person {
    void setGender(Gender gender);
    Gender getGender();
}

class PersonImpl implements Person {
    private Gender gender;

    @Override
    public void setGender(Gender gender) {
        this.gender = gender;
    }

    @Override
    public Gender getGender() {
        return this.gender;
    }
}