Stackoverflow OOPS design

package stackOverflow;

import java.util.Date;
import java.util.List;

public class StackOverFlow {

    public enum AccountStatus {
        ACTIVE, BLOCKED, BANNED, COMPROMISED, BLACKLISTED, CLOSED, CANCELLED;
    }

    public enum QuestionStatus {
        OPEN, CLOSE, DELETED, ONHOLD;
    }
    public enum QuestionClsoingTag {
        DUPLICATED, OFF_TOPIC, NOT_A_REAL_QUESTION, TOO_BROAD, INVALID;
    }

    public class Address {
        String street, city, state, country, pincode;

    }
    public class Account {
        String        userName;
        String        password;
        String        email;
        String        mobile;
        String        fullName;
        AccountStatus accountStatus;
        Address       address;
        Date          creationDate;
        int           reputation;

        // reset password

    }
    public class Badge {
        String name;
        String description;

    }
    public class Member {
        Account     accontDetails;
        List<Badge> badges;
        // create Question
        // setTag
        // getReputation
        // addAnswer
        // addCOmment
        // acceptAnswer
        // delete answer
        // undelete answer

    }
    public class Admin extends Member {
        // block memener
        // unblock member
    }
    public class Moderator extends Member {
        // delete question
        // undelete Question
    }

    public class Tag {
        String name;
        String description;
        int    noOfTimesUsedInQuestion;
        int    frequencyDaily;
        int    weeklyFrequnecy;
    }

    public class Bounty {
        int  reputation;
        Date expiryDate;

        // modifyExpiryDate
    }

    public class Photo {
        private int    photoId;
        private String photoPath;
        private Date   creationDate;

        private Member creatingMember;

        // public boolean delete();
    }

    public interface Search {
        List<Question> getQuestionListByQuery(String query);
    }
    public class Question implements Search {
        private String             title;
        private String             description;
        private int                viewCount;
        private int                voteCount;
        private Date               creationTime;
        private Date               updateTime;
        private QuestionStatus     status;
        private QuestionClsoingTag closingRemark;

        private Member             askingMember;
        private Bounty             bounty;
        List<Answer>               answers;
        List<Comment>              comments;
        List<Photo>                photos;

        // public boolean close();
        // public boolean undelete();
        // public boolean addComment(Comment comment);
        // public boolean addBounty(Bounty bounty);
        @Override
        public List<Question> getQuestionListByQuery(String query) {
            // TODO Auto-generated method stub
            return null;
        }
    }

    public class Answer {
        String          description;
        int             flagCOunt;
        int             voteCOunt;
        private Date    creationTime;
        private Date    updateTime;
        private Member  writingMember;
        private boolean accepted;
        List<Photo>     photos;
        // incrementVoteCOunt
    }

    public class Comment {
        String         text;
        int            flagCOunt;
        int            voteCOunt;
        private Date   creationTime;
        private Date   updateTime;
        private Member writingMember;
        List<Photo>    photos;
    }

}